What does the Bible teach?
What was that the teaching of early church leaders often venerated as saints by the Greco-Romans on this?
The terms immortal and immortality are not found in the Old Testament (NKJV).
Interestingly, Ezekiel recorded:
Behold, all souls are Mine;
The soul of the father
As well as the soul of the son is Mine;
The soul who sins shall die (Ezekiel 18:4).
Notice that Ezekiel says that souls that sin shall die. But since it is appointed unto men once to die (Hebrews 9:27), is this talking about the first or second death (Revelation 2:11;20:6,14;21:8)?
Well, notice the next several verses from Ezekiel:
But if a man is just And does what is lawful and right;
If he has not eaten on the mountains,Nor lifted up his eyes to the idols of the house of Israel,Nor defiled his neighbor’s wife, Nor approached a woman during her impurity;
If he has not oppressed anyone, But has restored to the debtor his pledge; Has robbed no one by violence, But has given his bread to the hungry And covered the naked with clothing;
If he has not exacted usury Nor taken any increase,But has withdrawn his hand from iniquity And executed true judgment between man and man;
If he has walked in My statutes And kept My judgments faithfully–He is just; He shall surely live!”Says the Lord GOD (Ezekiel 18:5-9).
Ezekiel is obviously talking about the first death.
Notice that the just man shall live. This is in contrast to the one who practices sin, who shall die. And, think about this point, the just man was already alive, hence the fact that he shall live suggests that God will resurrect him so that he can live forever.
Ezekiel basically continues and again warns:
The soul who sins shall die (Ezekiel 18:20).
These writings in the Old Testament seem to set the stage for the writings in the New Testament.
The New Testament
The New Testament teaches the same basic doctrines as the Old Testament, but tends to expand on them.
Jesus confirmed that souls can and will be destroyed when He taught:
And do not fear those who kill the body but cannot kill the soul. But rather fear Him who is able to destroy both soul and body (Matthew 10:28).
If souls were truly immortal, then they could not be destroyed. Jesus taught that death was like sleep:
11 These things He said, and after that He said to them, “Our friend Lazarus sleeps, but I go that I may wake him up.”
12 Then His disciples said, “Lord, if he sleeps he will get well.” 13 However, Jesus spoke of his death, but they thought that He was speaking about taking rest in sleep.
14 Then Jesus said to them plainly, “Lazarus is dead” (John 11:11-14).
Notice also that Jesus taught that eternal life was given at a later time, in the age to come:
29 Assuredly, I say to you, there is no one who has left house or parents or brothers or wife or children, for the sake of the kingdom of God, 30 who shall not receive many times more in this present time, and in the age to come everlasting life (Luke 18:29-30).
Thus, humans do not possess that eternal life now. The dead are asleep now:
14 Therefore He says:
“Awake, you who sleep,
Arise from the dead,
And Christ will give you light.” (Ephesians 5:14)
Perhaps the most famous passage in the New Testament is John 3:16. It states:
For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life.
Notice the contrast above. Humans would perish (and this means eternally, since all die physically) if God had not loved the world enough to send Jesus so that the believers could have everlasting life.
Paul clearly understood this concept as here is some of what he wrote about immortality:
1 Corinthians 15:51-54 51 Behold, I tell you a mystery: We shall not all sleep, but we shall all be changed — 52 in a moment, in the twinkling of an eye, at the last trumpet. For the trumpet will sound, and the dead will be raised incorruptible, and we shall be changed. 53 For this corruptible must put on incorruption, and this mortal must put on immortality. 54 So when this corruptible has put on incorruption, and this mortal has put on immortality, then shall be brought to pass the saying that is written: “Death is swallowed up in victory.” NKJV (1 Corinthians 15:51-54).
Notice that Paul is saying that we must be changed in order to possess immortality, and that the sleeping dead will be raised. And that this occurs at the resurrection. No human has immortality now.
Nor did Paul as he taught:
I have suffered the loss of all things, and count them as rubbish, that I may gain Christ and be found in Him, not having my own righteousness, which is from the law, but that which is through faith in Christ, the righteousness which is from God by faith; that I may know Him and the power of His resurrection, and the fellowship of His sufferings, being conformed to His death, if, by any means, I may attain to the resurrection from the dead.
Not that I have already attained, or am already perfected; but I press on, that I may lay hold of that for which Christ Jesus has also laid hold of me. Brethren, I do not count myself to have apprehended (Phillipians 3:8-13).
Thus, the immortality attained at the resurrection is not something that Christians have today.
Furthermore, all humans cannot possible possess immortality now. Look at what the Apostle John taught:
…you know that no murderer has eternal life abiding in him (1 John 3:15).
Since many people are or have been murderers, this proves that not all humans possess immortality.
Currently, look at who only has immortality:
He who is the blessed and only Potentate, the King of kings and Lord of lords, who alone has immortality (1 Timothy 6:15-16).
Thus, Jesus is the only one who was born human that who alone currently possesses immortality.
Other than the quotes above, the following are all the remaining times the NKJV uses the terms immortal or immortality:
…who “will render to each one according to his deeds”: eternal life to those who by patient continuance in doing good seek for glory, honor, and immortality (Romans 2:6-7).
…our Savior Jesus Christ, who has abolished death and brought life and immortality to light through the gospel (2 Timothy 1:10).
However, for this reason I obtained mercy, that in me first Jesus Christ might show all longsuffering, as a pattern to those who are going to believe on Him for everlasting life. Now to the King eternal, immortal (1 Timothy 1:16-17).
Note that every passage in the Bible that uses the terms immortal or immortality say that Jesus has immortality, that humans do not have it, that Jesus came so that humans can have it, and that He came to abolish death.
Why would this even be an issue if humans were already immortal?
Furthermore although some have used the term “soul sleep” in a negative manner towards those of us who believe that death is like sleep, notice what the Apostle Paul was inspired to write:
16 For if the dead do not rise, then Christ is not risen. 17 And if Christ is not risen, your faith is futile; you are still in your sins! 18 Then also those who have fallen asleep in Christ have perished. (1 Corinthians 15:16-18)
It is proper for Christians to teach and believe that death is like sleep. Those who condemn “soul sleep” are also condemning Jesus and the Apostle Paul.
Second Century Church Writings
But what about the early Church? After the apostles died (John being the last around 100 A.D.), there were early church writers who continued to teach what the apostles taught, which is what is in the Old and New Testaments. Many of the second century writings here are from true Church of God saints, and most of these writings are accepted as coming from “saints” according to the Greco-Roman churches.
Here is something from what is believed to be “the oldest complete Christian sermon that has survived” (Holmes M.W. Ancient Christian Sermon. The Apostolic Fathers: Greek Texts and English Translations, 2nd ed. Baker Books, Grand Rapids, 2004). This Ancient Christian Sermon contains these statements about it:
Now I do not think that I have given any mean council respecting continence, and whosoever performeth it will not repent thereof, but will save both himself and me his councilor. For it is no mean reward to convert a wondering and perishing soul, that it may be saved (15:1).
For if we have received commands, that we should make this our business, to tear men away from idols and to instruct them, how much more is it wrong that a soul which knoweth God already should perish! (17:1).
Souls that can perish cannot be immortal.
Notice this from Ignatius’ Letter to the Ephesians:
For this end did the Lord suffer the ointment to be poured upon His head, that He might breathe immortality into His Church (Chapter 17).
Especially [will I do this] if the Lord make known to me that ye come together man by man in common through grace, individually, in one faith, and in Jesus Christ, who was of the seed of David according to the flesh, being both the Son of man and the Son of God, so that ye obey the bishop and the presbytery with an undivided mind, breaking one and the same bread, which is the medicine of immortality, and the antidote to prevent us from dying, but [which causes] that we should live for ever in Jesus Christ (Chapter 20).
Ignatius is essentially teaching that Christ suffered to give immortality to the Church and we in the Church when we properly partake of Passover can live forever in Christ–otherwise we would die.
Be sober as an athlete of God: the prize set before you is immortality and eternal life, of which you are also persuaded (Ignatius. Letter to Polycarp, Chapter 2).
Polycarp of Smyrna (mid-2nd century) taught that the body and soul were to be resurrected, hence he taught against the immortality of the soul doctrine:
I bless you for because you have considered me worthy of this day and hour, that I might receive a place among the number of martyrs in the cup of your Christ, to the resurrection to eternal life, both of soul and of body, in the incorruptibility of the Holy Spirit (The Martyrdom of Polycarp, 14:2. In Holmes M.W. The Apostolic Fathers, Greek Texts and English Translations. Baker Books, Grand Rapids (MI), 2004, p.239).
Though the Greek Orthodox Church of Antioch now lists him in their succession list, around 170 A.D. Theophilus of Antioch wrote a position that seems to differ from current Eastern Orthodox doctrine on immortality:
When thou shalt have put off the mortal, and put on incorruption, then shall thou see God worthily. For God will raise thy flesh immortal with thy soul; and then, having become immortal, thou shalt see the Immortal, if now you believe on Him; and then you shall know that you have spoken unjustly against Him (Theophilus of Antioch. To Autolycus, Book 1, Chapter VI. Translated by Marcus Dods, A.M. Excerpted from Ante-Nicene Fathers, Volume 2. Edited by Alexander Roberts & James Donaldson. American Edition, 1885. Online Edition Copyright © 2004 by K. Knight).
For if He had made him immortal from the beginning, He would have made him God…so that if he should incline to the things of immortality, keeping the commandment of God, he should receive as reward from Him immortality, and should become God…For God has given us a law and holy commandments; and every one who keeps these can be saved, and, obtaining the resurrection, can inherit incorruption (Theophilus of Antioch. To Autolycus, Book 2, Chapter XXVII. Translated by Marcus Dods, A.M. Excerpted from Ante-Nicene Fathers, Volume 2. Edited by Alexander Roberts & James Donaldson. American Edition, 1885. Online Edition Copyright © 2004 by K. Knight).
But God at least, the Father and Creator of the universe did not abandon mankind, but gave a law, and sent holy prophets to declare and teach the race of men, that each one of us might awake and understand that there is one God. And they also taught us to refrain from unlawful idolatry, and adultery, and murder, fornication, theft, avarice, false swearing, wrath, and every incontinence and uncleanness; and that whatever a man would not wish to be done to himself, he should not do to another; and thus he who acts righteously shall escape the eternal punishments, and be thought worthy of the eternal life from God (Theophilus of Antioch. To Autolycus, Book 2, Chapter XXXIV. Translated by Marcus Dods, A.M. Excerpted from Ante-Nicene Fathers, Volume 2. Edited by Alexander Roberts & James Donaldson. American Edition, 1885. Online Edition Copyright © 2004 by K. Knight).
Probably prior to 180 A.D., Melito of Sardis, a famous church leader and writer, wrote:
He killed death which had put man to death (Melito. Homily On the Passover, Verse 66. Translation from Kerux: The Journal of Online Theology, http://www.kerux.com/documents/KeruxV4N1A1.asp 09/14/05). .
And by this, Melito is teaching that Jesus could provide immortality, as humans did not possess it (he obviously is not referring to physical death, as Christians have died throughout history).
Even though he held some heretical views, Irenaeus is considered to have been an important early theologian by Catholics and Protestants (around 180 A.D.) wrote, that:
Christ Jesus, our Lord, and God, and Saviour, and King…may, in the exercise of His grace, confer immortality on the righteous, and holy, and those who have kept His commandments (Irenaeus. Adversus haereses, Book 1, Chapter 10, Verse 1. Excerpted from Ante-Nicene Fathers, Volume 1. Edited by Alexander Roberts & James Donaldson. American Edition, 1885. Online Edition Copyright © 2004 by K. Knight).
Thus Irenaeus did understand the idea that humans do not possess immortality and that it is a gift of God. And this gift is only given to those that have kept His commandments.
He also understood that the resurrection was physical:
We therefore have formed the belief that [our] bodies also do rise again. For although they go to corruption, yet they do not perish; for the earth, receiving the remains, preserves them, even like fertile seed mixed with more fertile ground. Again, as a bare grain is sown, and, germinating by the command of God its Creator, rises again, clothed upon and glorious, but not before it has died and suffered decomposition, and become mingled with the earth (Irenaeus. Fragments of Irenaeus, Fragment VII. Translated by Alexander Roberts and James Donaldson. Excerpted from Volume I of The Ante-Nicene Fathers (Alexander Roberts and James Donaldson, editors); American Edition copyright © 1885. Electronic version copyright © 1997 by New Advent, Inc.).
And even though he was not part of the true Church of God, Justin wrote:
Justin also stated, “For I choose to follow not men or men’s doctrines, but God and the doctrines [delivered] by Him. For if you have fallen in with some who are called Christians, but who do not admit this [truth], and venture to blaspheme the God of Abraham, and the God of Isaac, and the God of Jacob; who say there is no resurrection of the dead, and that their souls, when they die, are taken to heaven; do not imagine that they are Christians” (Dialogue. Chapter 80).
While those of us in the Continuing Church of God would agree that souls die (Ezekiel 18:4) and are not taken to heaven upon death (Job:14:14; John 3:13), those in the Catholic, Orthodox, and Protestant churches would seem to disagree with Justin here.
The second century apologist Tatian and associate of Justin wrote:
The soul is not in itself immortal, O Greeks, but mortal. Yet it is possible for it not to die. If, indeed, it knows not the truth, it dies, and is dissolved with the body, but rises again at last at the end of the world with the body, receiving death by punishment in immortality (Tatian. Translated by J.E. Ryland. Tatian’s Address to the Greeks, Chapter XIII . Excerpted from Ante-Nicene Fathers, Volume 2. Edited by Alexander Roberts & James Donaldson. American Edition, 1885. Online Edition Copyright © 2004 by K. Knight).
Polycrates of Ephesus in the late second century wrote and told the Roman Bishop Victor:
Why need I mention the bishop and martyr Sagaris who fell asleep in Laodicea, or the blessed Papirius, or Melito, the Eunuch who lived altogether in the Holy Spirit, and who lies in Sardis, awaiting the episcopate from heaven, when he shall rise from the dead? (Eusebius. Church History, Book V, Chapter 24, Verse 5. Translated by Arthur Cushman McGiffert. Excerpted from Nicene and Post-Nicene Fathers, Series Two, Volume 1. Edited by Philip Schaff and Henry Wace. American Edition, 1890. Online Edition Copyright © 2004 by K. Knight).
Thus immortality was something to be obtained, not something inherent. And the idea of man’s destiny to become God was known in the second century.
Tertullian was a second century religious leader outside the Church of God. And although he held doctrines that we in the COGs would find to be heretical, he is considered to have been an important early theologian by Roman Catholics. Tertullian wrote:
The resurrection is first, and afterwards the kingdom. We say, therefore, that the flesh rises again, but that when changed it obtains the kingdom. “For the dead shall be raised incorruptible,” even those who had been corruptible when their bodies fell into decay; “and we shall be changed, in a moment, in the twinkling of an eye. For this corruptible”–and as he spake, the apostle seemingly pointed to his own flesh–” must put on incorruption, and this mortal must put on immortality.” in order, indeed, that it may be rendered a fit substance for the kingdom of God. “For we shall be like the angels.” This will be the perfect change of our flesh–only after its resurrection. Now if, on the contrary, there is to be no flesh, how then shall it put on incorruption and immortality? Having then become something else by its change, it will obtain the kingdom of God, no longer the (old) flesh and blood, but the body which God shall have given it. Rightly then does the apostle declare, “Flesh and blood cannot inherit the kingdom of God;” for this (honour) does he ascribe to the changed condition which ensues on the resurrection (Tertullian. Against Marcion, Book V, Chapter 10. Excerpted from Ante-Nicene Fathers, Volume 3. Edited by Philip Schaff, D.D., LL.D. American Edition, 1885. Online Edition Copyright © 2005 by K. Knight).
Thus, he is correctly teaching that we are not now immortal and not as we now are fit for the kingdom of God–this occurs after the resurrection.
The Catholic bishop Hippolytus was a third century religious leader outside the Church of God. And although he held doctrines that we in the COGs would find to be heretical, he is considered to have been one of the greatest early theologians by Roman Catholics.
Let us believe then, dear brethren, according to the tradition of the apostles, that God the Word came down from heaven, (and entered) into the holy Virgin Mary, in order that, taking the flesh from her, and assuming also a human, by which I mean a rational soul, and becoming thus all that man is with the exception of sin, He might save fallen man, and confer immortality on men who believe on His name (Hippolytus. Against Noetus, Chapter 17. Excerpted from Ante-Nicene Fathers, Volume 5. Edited by Alexander Roberts & James Donaldson. American Edition, 1886. Online Edition Copyright © 2005 by K. Knight).
Notice that Hippolytus taught that Jesus needed to come in order to confer immortality on men. He would not have to do that if humans were immortal.
Hippolytus also wrote:
For concerning the general resurrection and the kingdom of the saints, Daniel says: “And many of them that sleep in the dust of the earth shall awake, some to everlasting life, and some to shame and everlasting contempt.” And Isaiah says: “The dead shall rise, and those in the tombs shall awake, and those in the earth shall rejoice.” And our Lord says: “Many in that day shall hear the voice of the Son of God, and they that hear shall live” (Hippolytus. On the End of the World, Chapter XXXVI. Excerpted from Ante-Nicene Fathers, Volume 5. Edited by Alexander Roberts & James Donaldson. American Edition, 1886. Online Edition Copyright © 2005 by K. Knight).
Notice that Hippolytus is showing that death is like sleep and the dead must be raised.
The Catholic bishop Victorinus (ca. late third century) wrote:
“To him that overcomes I will give the hidden manna, and I will give him a white stone.” The hidden manna is immortality; the white gem is adoption to be the son of God; the new name written on the stone is “Christian.” (Victorinus. Commentary on the Apocalypse. Translated by Robert Ernest Wallis. From Ante-Nicene Fathers, Vol. 7. Edited by Alexander Roberts, James Donaldson, and A. Cleveland Coxe. (Buffalo, NY: Christian Literature Publishing Co., 1886.) Revised and edited for New Advent by Kevin Knight. <http://www.newadvent.org/fathers/0712.htm> viewed 12/27/08)
There would be no reason to give immortality if it was possessed upon birth.
Pertaining to peoples in the third century, Eusebius about wrote that some in Arabia:
They said that during the present time the human soul dies and perishes with the body, but that at the time of the resurrection they will be renewed together (Eusebius. Church History, Book VI, Chapter 37).
The immortality of the soul doctrine seemed to enter the Greco-Roman churches from compromises with paganism and likely originated in Egypt. A spurious document apparently from the second or early third century may have been used to introduce the immortality heresy into the Alexandrian Orthodox:
Now, the proof that the soul is immortal will be put past doubt, not from what it says, or from what I hear, but from what I see: for seeing it with my eyes, I shall ever after hold the surest conviction of its immortality; and no fallacy of words or uncertainty of hearing shall ever be able to disturb the persuasion produced by sight. (The Recognitions of Clement, 1.5. In the Ante-Nicene Fathers, Rev. Alexander Roberts and James Donaldson, editors, Vol. VIII. Grand Rapids, Michigan: Wm. B Eerdmans Publishing Company, reprinted 1995. Note: This text is considered to have been spurious and probably not written by Clement of Alexandria. It seems to be a second century document and could have impacted the views of Gregory the Wonder Worker and others.)
Notice that the claim for immortality above is NOT based on the Bible, but what the author claims to see. The Bible teaches that we are to “walk by faith, not by sight” (2 Corinthians 5:7)–yet perhaps the first “pro-immortality” Greco-Roman writing does not appeal to scripture, unlike the future immorality writers generally did.
Since it is believed that Origen referred to this Recognition work c. 231, he would have been familiar with it, though some believe passages may have been added to it in the fourth or even later centuries (Smith T. Introductory Notice to The Recognitions of Clement. ANTE-NICENE FATHERS VOLUME 8. The Twelve Patriarchs, Excerpts and Epistles, The Clementina, Apocrypha, Decretals, Memoirs of Edessa and Syriac Documents, Remains of the First Ages Edited by ALEXANDER ROBERTS, D.D., and JAMES DONALDSON, LL.D. Revised and Chronologically Arranged, with Brief Prefaces and Occasional Notes by A. CLEVELAND COXE, D.D. T&T CLARK EDINBURGH, pp. 73-74).
But it should be noted that in the mid-late third century a mystic often now referred to as Gregory the Wonder Worker. Gregory studied under Origen in Alexandria Egypt. Gregory was the first to claim to see “Mary,” helped introduce heretical doctrines, and may have been the first of the Greco-Roman bishops to teach that the soul was immortal:
We prove, then, that the soul is simple…that what is simple is immortal…If, therefore, the soul is not corrupted by the evil proper to itself, and the evil of the soul is cowardice, intemperance, envy, and the like, and all these things do not despoil it of its powers of life and action, it follows that it is immortal. (Gregory Thaumaturgus. On the Soul, Chapters 5, 6. Translated by S.D.F. Salmond. From Ante-Nicene Fathers, Vol. 6. Edited by Alexander Roberts, James Donaldson, and A. Cleveland Coxe. Buffalo, NY: Christian Literature Publishing Co., 1886. Revised and edited for New Advent by Kevin Knight. <http://www.newadvent.org/fathers/0608.htm> viewed 06/05/11)
Sand is simple, but that does not make it immortal, yet the simplicity argument is supposedly proof of the false doctrine.
And while this doctrine was not commonly accepted for a while, his change did get accepted (though to a significant degree because of others, but also likely some he at least indirectly affected). But it never should have been accepted. in Ezekiel 18:4 the Douay-Rheims Bible (a well known Roman Catholic rendition of scripture into the English language) teaches ” the soul that sinneth, the same shall die” and “The soul that sinneth, the same shall die” in Ezekiel 18:20.
Athanasius was a fourth century religious leader outside the Church of God. And although he held doctrines that we in the COGs would find to be heretical (including some held by Gregory Thaumagutus), he is considered to be a major saint and historical figure by the Roman Catholics and Eastern Orthodox.
But even he understood the concept that after the resurrection, that Christians were to become God and that they had to inherit immortality, as man otherwise is mortal. Notice what he wrote:
…that by death immortality has reached to all, that by the Word becoming man, the universal Providence has been known, and its Giver and Artificer the very Word of God. 3. For He was made man that we might be made God; and He manifested Himself by a body that we might receive the idea of the unseen Father; and He endured the insolence of men that we might inherit immortality (Athanasius. On the Incarnation of the Word, Chapter 54, Verses 2-3. Excerpted from Nicene and Post-Nicene Fathers, Second Series, Volume 4. Edited by Philip Schaff and Henry Wace. American Edition, 1892. Online Edition Copyright © 2005 by K. Knight).
…for us, that us who are mortal and temporal, the Lord, become man, might make immortal, and bring into the everlasting kingdom of heaven? (Athanasius. Discourse I Against the Arians, Chapter 48, Verse 1. Excerpted from Nicene and Post-Nicene Fathers, Second Series, Volume 4. Edited by Philip Schaff and Henry Wace. American Edition, 1892. Online Edition Copyright © 2005 by K. Knight).
‘The Word became flesh,’ that He might make man capable of Godhead…He created us, the Economy of our salvation; that though by the serpent’s deceit we fell from Him, we might not remain quite dead, but having in the Word the redemption and salvation which was afore prepared for us, we might rise again and abide immortal, what time He should have been created for us ‘a beginning of the ways,’ and He who was the ‘First-born of creation’ should become ‘first-born’ of the ‘brethren,’ and again should rise ‘first-fruits of the dead.’ (Athanasius. Discourse I Against the Arians, Chapters 59,75. Excerpted from Nicene and Post-Nicene Fathers, Second Series, Volume 4. Edited by Philip Schaff and Henry Wace. American Edition, 1892. Online Edition Copyright © 2005 by K. Knight).
The fourth century Catholic apologist and teacher Lactantius wrote:
For since man consists of two parts, body and soul, of which the one is earthly, the other heavenly, two lives have been assigned to man: the one temporal, which is appointed for the body; the other everlasting, which belongs to the soul. We received the former at our birth we attain to the latter by striving, that immortality might not exist to man without any difficulty. That earthly one is as the body, and therefore has an end; but this heavenly one is as the soul, and therefore has no limit. We received the first when we were ignorant of it, this second knowingly; for it is given to virtue, not to nature, because God wished that we should procure life for ourselves in life.
For this reason He has given us this present life, that we may either lose that true and eternal life by our vices, or win it by virtue…For other animals incline towards the ground, because they are earthly, and are incapable of immortality, which is from heaven; but man is upright and looks towards heaven, because immortality is proposed to him; which, however, does not come, unless it is given to man by God. For otherwise there would be no difference between the just and the unjust, since every man who is born would become immortal. Immortality, then, is not the consequence of nature, but the reward and recompense of virtue…God seeks to be worshipped, and to be honoured by man as a Father, that he may have virtue and wisdom, which alone produce immortality. For because no other but Himself is able to confer that immortality, since He alone possesses it, He will grant to the piety of the man, with which he has honoured God, this reward, to be blessed to all eternity, and to be for ever in the presence of God and in the society of God (Lactantius. Divine Institutes, Book VII, Of a Happy Life, Chapter 5).
The fourth century, Bishop Ambrose of Milan wrote:
The third death is that of which it is said: “Leave the dead to bury their own dead.” In that death not only the flesh but also the soul dies, for “the soul that sinneth, it shall die.” For it dies to the Lord, through the weakness not of nature but of guilt. But this death is not the discharge from this life, but a fall through error…The heathen mostly console themselves with the thought, either of the common misery, or of the law of nature, or of the immortality of the soul. And would that their utterances were consistent, and that they did not transmit the wretched soul into a number of ludicrous monstrosities and figures!
But what ought we to do, whose reward is the resurrection, though many, not being able to deny the greatness of this gift, refuse to believe in it? And for this reason will we maintain it, not by one casual argument only, but by as many as we are able…The blossom of the resurrection is immortality, the blossom of the resurrection is incorruption (Ambrose of Milan. Book II. On the Belief in the Resurrection, verses 37, 50, 54).
Thus even into the fourth century, the immortality of humans was not taught as is now accepted by Catholics and Protestants. But this seemed to change as many who professed Catholicism ended coming from a background in Mithraism (such as Emperor Constantine).
Mithraism Taught the Immortality of the Soul
In the fourth century, there was a sort of merging between the Greco-Roman churches and many who had been followers of the sun-god Mithras. And while the Greco-Romans did not adopt everything associated with Mithraism, they did adopt some practices and beliefs that those who followed Mithras had.
While many Roman emperors had been followers of Mithras, they tended to distain forms of Christianity. However this changed with Emperor Constantine.
The Catholic Encyclopedia reports:
…it was especially in the western part of the empire that the veneration of Mithras predominated. Would it not be possible to gather all the different nationalities around his altars? Could not Sol Deus Invictus, to whom even Constantine dedicated his coins for a long time, or Sol Mithras Deus Invictus, venerated by Diocletian and Galerius, become the supreme god of the empire? Constantine may have pondered over this. Nor had he absolutely rejected the thought even after a miraculous event had strongly influenced him in favour of the God of the Christians…As pontifex maximus he watched over the heathen worship and protected its rights…It is true that the believers in Mithras also observed Sunday as well as Christmas. Consequently Constantine speaks not of the day of the Lord, but of the everlasting day of the sun.
(Herbermann, Charles, and Georg Grupp. “Constantine the Great.” The Catholic Encyclopedia. Vol. 4. New York: Robert Appleton Company, 1908. 1 Sept. 2008 <http://www.newadvent.org/cathen/04295c.htm>)
It should be mentioned that the coins dedicated to Mithras still were produced for years after Constantines’ alleged acceptance of “Christianity”.
Mithraism taught the immortality of the soul. And though that was not the original position of the Greco-Roman churches, scholars recognize that both Mithraism and mainstream Christianity ended up with a similar teaching on this subject:
The resemblances between Mithraism and Christianity may be quickly summed up,—belief in the immortality of the soul (Aiken C.F., Mithraism and Christianity. The Catholic University bulletin, Volume 19, 1913. Original from the University of Michigan, Digitized Dec 19, 2008, p. 380)
They both admitted the existence of a Heaven inhabited by beatified ones, situate in the upper regions…they both, finally, believed in the immortality of the soul (Cumont, Franz. Translated from the second revised French edition by Thomas J. McCormack. The Mysteries of Mithra. Chicago, OThe Catholic University bulletin Author Catholic University of America Publisher Catholic University of America., 1913 Item notes v. 19 Original from the University of Michigan Digitized Dec 19, 2008pen Court  p. 193).
Because of Emperor Constantine’s strong influence (perhaps also combined with Gregory the Wonder Worker’s writings), it should be little surprise that the Greco-Romans began to change to accept a teaching that they original taught against. But for a while, the “immortality of the soul” view was in the minority.
Others also noticed some of this. Here is some of what the late Martin Luther King, Jr. wrote about it in a paper dated November 23, 1949:
In Avesta, Mithra was the genius of celestial light…The doctrine of the immortality of the soul was another view which was very prominent in Mithraism…Of all the mystery cults, Mithraism was the greatest competitor of Christianity…That Christians did copy and borrow from Mithraism cannot be denied (King ML. The papers of Martin Luther King, Jr, Volume 4. Clayborne Carson, Ralph Luker, Penny A. Russell editors/compliers. University of California Press, 1992, pp. 213-214, 217, 222, 224).
So, immortality of the soul was a prominent view within Mithraism and the Greco-Romans adopted it for their form of “Christianity”. (For more on Mithraism, please check out Do You Practice Mithraism?)
Some articles to assist in your studies may include:
Did Early Christians Believe that Humans Possessed Immortality? What does John 3:16, and other writings, tell us? Did a doctrine kept adopted from paganism? Here is a YouTube video titled Are humans immortal?
Nazarene Christianity: Were the Original Christians Nazarenes? Should Christians be Nazarenes today? What were the practices of the Nazarenes.
Early Church History: Who Were the Two Major Groups Professed Christ in the Second and Third Centuries? Did you know that many in the second and third centuries felt that there were two major, and separate, professing Christian groups in the second century, but that those in the majority churches tend to now blend the groups together and claim “saints” from both? “Saints” that condemn some of their current beliefs. Who are the two groups?
Do You Practice Mithraism? Many practices and doctrines that mainstream so-called Christian groups have are the same or similar to those of the sun-god Mithras. December 25th was celebrated as his birthday. Do you follow Mithraism combined with the Bible or original Christianity?
Hope of Salvation: How the Continuing Church of God differ from most Protestants How the real Church of God differs from mainstream/traditional Protestants, is perhaps the question I am asked most by those without a Church of God background.
Some Similarities and Differences Between the Eastern Orthodox Church and the Continuing Church of God Both groups claim to be the original church, but both groups have differing ways to claim it. Both groups have some amazing similarities and some major differences. Do you know what they are?
Which Is Faithful: The Roman Catholic Church or the Continuing Church of God? Do you know that both groups shared a lot of the earliest teachings? Do you know which church changed? Do you know which group is most faithful to the teachings of the apostolic church? Which group best represents true Christianity? This documented article answers those questions.
Continuing Church of God The group striving to be most faithful amongst all real Christian groups to the word of God.
The History of Early Christianity Are you aware that what most people believe is not what truly happened to the true Christian church? Do you know where the early church was based? Do you know what were the doctrines of the early church? Is your faith really based upon the truth or compromise?