On The Holy Trinity by St. Augustine
Chapter 11.--The Image of the Beast in Man.
16. For as a snake does not creep on with open steps, but advances by the very minutest efforts of its several scales; so the slippery motion of falling away [from what is good] takes possession of the negligent only gradually, and beginning from a perverse desire for the likeness of God, arrives in the end at the likeness of beasts. Hence it is that being naked of their first garment, they earned by mortality coats of skins. For the true honor of man is the image and likeness of God, which is not preserved except it be in relation to Him by whom it is impressed. The less therefore that one loves what is one's own, the more one cleaves to God. But through the desire of making trial of his own power, man by his own bidding falls down to himself as to a sort of intermediate grade. And so, while he wishes to be as God is, that is, under no one, he is thrust on, even from his own middle grade, by way of punishment, to that which is lowest, that is, to those things in which beasts delight: and thus, while his honor is the likeness of God, but his dishonor is the likeness of the beast, |Man being in honor abideth not: he is compared to the beasts that are foolish, and is made like to them.| By what path, then, could he pass so great a distance from the highest to the lowest, except through his own intermediate grade? For when he neglects the love of wisdom, which remains always after the same fashion, and lusts after knowledge by experiment upon things temporal and mutable, that knowledge puffeth up, it does not edify: so the mind is overweighed and thrust out, as it were, by its own weight from blessedness; and learns by its own punishment, through that trial of its own intermediateness, what the difference is between the good it has abandoned and the bad to which it has committed itself; and having thrown away and destroyed its strength, it cannot return, unless by the grace of its Maker calling it to repentance, and forgiving its sins. For who will deliver the unhappy soul from the body of this death, unless the grace of God through Jesus Christ our Lord? of which grace we will discourse in its place, so far as He Himself enables us.