The Enchiridion

Nor does the earthly material out of which men's mortal bodies are created ever perish; but though it may crumble into dust and ashes, or be dissolved into vapors and exhalations, though it may be transformed into the substance of other bodies, or dispersed into the elements, though it should become food for beasts or men, and be changed into their flesh, it returns in a moment of time to that human soul which animated it at the first, and which caused it to become man, and to live and grow.