I. Nature of the soul
II. Distinction between the body and the soul

I. Nature of the soul (Top)

And the very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ. 1 Thessalonians 5:23

For reflect upon the end of each of the preceding kings, how they died the death common to all, which, if it issued in insensibility, would be a godsend to all the wicked. But since sensation remains to all who have ever lived, and eternal punishment is laid up (i.e., for the wicked), see that you neglect not to be convinced, and to hold as your belief, that these things are true. For let even necromancy, and the divinations you practice by immaculate children, and the evoking of departed human souls, and those who are called among the magi, Dream-senders and Assistant-spirits (Familiars), and all that is done by those who are skilled in such matters - let these persuade you that even after death souls are in a state of sensation. Justin Martyr (A.D. 160) Ante-Nicene Fathers vol.1 pg.169

Now the soul and the spirit are certainly a part of the man, but certainly not the man; for the perfect man consists in the commingling and the union of the soul receiving the spirit of the Father, and the admixture of that fleshly nature which was molded after the image of God. Irenaeus (A.D. 180) Ante-Nicene Fathers vol.1 pg. 531

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. But, again, if it acquires the knowledge of God, it dies not, although for a time it be dissolved. In itself it is darkness, and there is nothing luminous in it. And this is the meaning of the saying, "The darkness comprehends not the light." For the soul does not preserve the spirit, but is preserved by it, and the light comprehends the darkness. Tatian (A.D.160) Ante-Nicene Fathers vol.2 pg.70

Pleasure has often produced in men harm and pain; and full feeding begets in the soul uneasiness, and forgetfulness, and foolishness. Clement of Alexandria (A.D. 195) Ante-Nicene Fathers vol.2 pg.242

All souls are immortal, even those of the wicked, for whom it were better that they were not deathless. For, punished with the endless vengeance of quenchless fire, and not dying, it is impossible for them to have a period put to their misery. Clement of Alexandria (A.D. 195) Ante-Nicene Fathers vol.2 pg.581

In the Gospel itself they will be found to have the clearest evidence for the corporeal nature of the soul. In hell the soul of a certain man is in torment, punished in flames, suffering excruciating thirst, and imploring from the finger of a happier soul, for his tongue, the solace of a drop of water. Do you suppose that this end of the blessed poor man and the miserable rich man is only imaginary? … Therefore, whatever amount of punishment or refreshment the soul tastes in Hades, in its prison or lodging, in the fire or in Abraham's bosom, it gives proof thereby of its own corporeality. For an incorporeal thing suffers nothing, not having that which makes it capable of suffering; else, if it has such capacity, it must be a bodily substance. For in as far as every corporeal thing is capable of suffering, in so far is that which is capable of suffering also corporeal. Tertullian (A.D. 198) Ante-Nicene Fathers vol.3 pg. 186-187

II. Distinction between the body and the soul (Top)

In a word, what the soul is in a body, this the Christians are in the world. The soul is spread through all the members of the body, and Christians through the divers cities of the world. The soul has its abode in the body, and yet it is not of the body. So Christians have their abode in the world, and yet they are not of the world. The soul which is invisible is guarded in the body which is visible: so Christians are recognized as being in the world, and yet their religion remains invisible. The flesh hates the soul and wages war with it, though it receives no wrong, because it is forbidden to indulge in pleasures; so the world hates Christians, though it receives no wrong from them, because they set themselves against its pleasures. The soul loves the flesh which hates it, and the members: so Christians love those that hate them. The soul is enclosed in the body, and yet itself holds the body together; so Christians are kept in the world as in a prison-house, and yet they themselves hold the world together. The soul though itself immortal dwells in a mortal tabernacle; so Christians sojourn amidst perishable things, while they look for the imperishability which is in the heavens. The soul when hardly treated in the matter of meats and drinks is improved; and so Christians when punished increase more and more daily. Letter to Diognetus (A.D. 125-200) ch.6

The soul assuredly is or has life. If, then, it is life, it would cause something else, and not itself, to live, even as motion would move something else than itself. Now, that the soul lives, no one would deny. But if it lives, it lives not as being life, but as the partaker of life; but that which partakes of anything, is different from that of which it does partake. Now the soul partakes of life, since God wills it to live. Thus, then, it will not even partake [of life] when God does not will it to live. For to live is not its attribute, as it is God's; but as a man does not live always, and the soul is not for ever conjoined with the body, since, whenever this harmony must be broken up, the soul leaves the body, and the man exists no longer; even so, whenever the soul must cease to exist, the spirit of life is removed from it, and there is no more soul, but it goes back to the place from whence it was taken. Justin Martyr (A.D. 160) Ante-Nicene Fathers vol.1 pg.198

Quite true, say they; yet the flesh is a sinner, so much so, that it forces the soul to sin along with it. And thus they vainly accuse it, and lay to its charge alone the sins of both. But in what instance can the flesh possibly sin by itself, if it have not the soul going before it and inciting it? For as in the case of a yoke of oxen, if one or other is loosed from the yoke, neither of them can plough alone; so neither can soul or body alone effect anything, if they be unyoked from their communion. Justin Martyr (A.D. 160) Ante-Nicene Fathers vol.1 pg.297

The resurrection is a resurrection of the flesh which died. For the spirit dies not; the soul is in the body, and without a soul it cannot live. The body, when the soul forsakes it, is not. For the body is the house of the soul; and the soul the house of the spirit. These three, in all those who cherish a sincere hope and unquestioning faith in God, will be saved. Justin Martyr (A.D. 160) Ante-Nicene Fathers vol.1 pg. 298

And there is a ten in man himself: the five senses, and the power of speech, and that of reproduction; and the eighth is the spiritual principle communicated at his creation; and the ninth the ruling faculty of the soul; and tenth, there is the distinctive characteristic of the Holy Spirit, which comes to him through faith. Clement of Alexandria (A.D. 195) Ante-Nicene Fathers vol.2 pg.511

But the operation of death is plain and obvious: it is the separation of body and soul. Tertullian (A.D. 198) Ante-Nicene Fathers vol.3 pg. 228