Nevertheless one who regards only the dissolution of the body is greatly disturbed, and makes it a hardship that this life of ours should be dissolved by death; it is, he says, the extremity of evil that our being should be quenched by this condition of mortality. Let him, then, observe through this gloomy prospect the excess of the Divine benevolence. He may by this, perhaps, be the more induced to admire the graciousness of God's care for the affairs of man. To live is desirable to those who partake of life, on account of the enjoyment of things to their mind; since, if any one lives in bodily pain, not to be is deemed by such an one much more desirable than to exist in pain.
Let us inquire, then, whether He Who gives us our outfit for living has any other object in view than how we may pass our life under the fairest circumstances. Now since by a motion of our self-will we contracted a fellowship with evil, and, owing to some sensual gratification, mixed up this evil with our nature like some deleterious ingredient spoiling the taste of honey, and so, falling away from that blessedness which is involved in the thought of passionlessness, we have been viciously transformed— for this reason, Man, like some earthen potsherd, is resolved again into the dust of the ground, in order to secure that he may part with the soil which he has now contracted, and that he may, through the resurrection, be reformed anew after the original pattern; at least if in this life that now is he has preserved what belongs to that image.
A doctrine such as this is set before us by Moses under the disguise of an historical manner. And yet this disguise of history contains a teaching which is most plain. For after, as he tells us, the earliest of mankind were brought into contact with what was forbidden, and thereby were stripped naked of that primal blessed condition, the Lord clothed these, His first-formed creatures, with coats of skins. In my opinion we are not bound to take these skins in their literal meaning.
For to what sort of slain and flayed animals did this clothing devised for these humanities belong? But since all skin, after it is separated from the animal, is dead, I am certainly of opinion that He Who is the healer of our sinfulness, of His foresight invested man subsequently with that capacity of dying which had been the special attribute of the brute creation. Not that it was to last for ever; for a coat is something external put on us, lending itself to the body for a time, but not indigenous to its nature.
This liability to death, then, taken from the brute creation, was, provisionally, made to envelope the nature created for immortality. It enwrapped it externally, but not internally. It grasped the sentient part of man; but laid no hold upon the Divine image. This sentient part, however, does not disappear, but is dissolved. Disappearance is the passing away into non-existence, but dissolution is the dispersion again into those constituent elements of the world of which it was composed. But that which is contained in them perishes not, though it escapes the cognisance of our senses.
Source: The Great Catechism (New Advent)