The Early Church Fathers on various topics: This was a 3700 hour project which included going through 22896 pages of the 38 volume set called Ante Nicene, Nicene, Post Nicene Fathers. I compiled 255 pages of quotes showing that the Early Church was always and completely Catholic. All of these quotes can be verified and found from the source which is free online.
Justin Martyr Fragments on the resurrection ch 8 (100-165 ad)
Well, they say, but the soul is incorruptible, being a part of God and inspired by Him, and therefore He desires to save what is peculiarly His own and akin to Himself; but the flesh is corruptible, and not from Him, as the soul is. Then what thanks are due to Him, and what manifestation of His power and goodness is it, if He purposed to save what is by nature saved and exists as a part of Himself? For it had its salvation from itself; so that in saving the soul, God does no great thing. For to be saved is its natural destiny, because it is a part of Himself, being His inspiration. But no thanks are due to one who saves what is his own; for this is to save himself. For he who saves a part himself, saves himself by his own means, lest he become defective in that part; and this is not the act of a good man. For not even when a man does good to his children and offspring, does one call him a good man; for even the most savage of the wild beasts do so, and indeed willingly endure death, if need be, for the sake of their cubs.
Clement of Alexandria The instructor book 1 ch 6 (150-215 ad)
Being baptized, we are illuminated; illuminated, we become sons; being made sons, we are made perfect; being made perfect, we are made immortal. "I," says He, "have said that ye are gods, and all sons of the Highest." This work is variously called grace, and illumination, and perfection, and washing: washing, by which we cleanse away our sins; grace, by which the penalties accruing to transgressions are remitted; and illumination, by which that holy light of salvation is beheld, that is, by which we see God clearly. Now we call that perfect which wants nothing.
Tertullian Ad Nationes Book 2 ch 3 (160-240 ad)
But if this be the case, they must needs be also mortal, according to the condition of animated nature; for although the soul is evidently immortal, this attribute is limited to it alone: it is not extended to that with which it is associated, that is, the body
Hyppolytus Discourse on the Holy Theophany par 10 (170-236 ad)
The Father of immortality sent the immortal Son and Word into the world, who came to man in order to wash him with water and the Spirit; and He, begetting us again to incorruption of soul and body, breathed into us the breath (spirit) of life, and endued us with an incorruptible panoply. If, therefore, man has become immortal, he will also be God. And if he is made God by water and the Holy Spirit after the regeneration of the layer he is found to be also joint-heir with Christ after the resurrection from the dead. Wherefore I preach to this effect: Come, all ye kindreds of the nations, to the immortality of the baptism.
Hippolytus Refutation of All Heresies book 10 ch 30 (170-236 ad)
And thou shalt possess an immortal body, even one placed beyond the possibility of corruption, just like the soul.
Origen de Principiis book 3 ch 1.18 (185- 254 ad)
Whence we are of opinion that, seeing the soul, as we have frequently said, is immortal and eternal,
Origen de Principiis book 3 ch 1.17 (185- 254 ad)
by striving to show that the providence of God, which equitably administers all things, governs also immortal souls on the justest principles, (conferring rewards) according to the merits and motives of each individual
Eusebius of Caesarea Oration in Praise of Constantine (265-340 ad)
Who has instructed barbarians and peasants, yea, feeble women, slaves, and children, in short, unnumbered multitudes of all nations, to live in the contempt of death; persuaded of the immortality of their souls
Eusebius of Caesarea Life of Constantine book 1 ch 3 (265-340 ad)
All these indeed are perishable, and consumed by the lapse of time, being representations of the corruptible body, and not expressing the image of the immortal soul
Athanasius Against the Heathen par 33 (296-373)
The soul immortal. Proved by (I) its being distinct from the body, (2) its being the source of motion, (3) its power to go beyond the body in imagination and thought. But that the soul is made immortal is a further point in the Church's teaching which you must know,
Methodius Discourse on the Resurrection par 12 (300 ad)
But it is the flesh which dies; the soul is immortal.
John Chrysostom Homily 31 on John’s gospel (347-407 ad)
Things irrational only are useful for the present life; but we have an immortal soul, that we may use every means to prepare ourselves for that other life.
Augustine Tractate 15 on the gospel of John (354-430 ad)
What is it for thee to have a soul? It is not much, for a beast has a soul.
Theodoret of Cyrus Dialogue 3 (393-457 ad)
Orth. -- And when we read in the Acts how Herod slew James the brother of John with a sword, we are not likely to hold that his soul died. [+] Eran. --No; how could we? We remember the Lord's warning "Fear not them which kill the body but are not able to kill the soul." [R] [+] Orth. -- But does it not seem to you impious and monstrous in the case of mere men to avoid the invariable connexion of soul and body, and in the case of scriptural references to death and burial, to distinguish in thought the soul from the body and connect them only with the body, while in trust in the teaching of the Lord you hold the sold to be immortal