They deal with errors against which Chrysostom throughout his life most strenuously contended. In an age of great depravity there seem to have been many who tried to excuse the weak resistance which they made to evil, both in themselves, and in others, by maintaining that the world was abandoned to the dominion of devils, or to the irresistible course of fate. To counteract the disastrous effects of such philosophy, which surrendered man to the current of his passions, it was necessary to insist very boldly and resolutely on the essential freedom of the will, on moral responsibility, and the duty of vigorous exertion in resisting temptation. And Chrysostom did this to an extent which some thought carried him perilously near the errors of the Pelagian heresy. No one however has described in more forcible language the powerful hold of sin upon human nature, and the insufficiency of man to shake it off without the assistance of divine grace. What he does most earnestly combat, both in the following homilies and very many others, is the doctrine that evil was an original integral part of our nature: he maintains that it is not a substantial inherent force (δύναμις ἐνυπόστατος). If evil was a part of our nature in this sense it would be no more reprehensible than natural appetites and affections. We do not try to alter that which is by nature (φύσει): sin therefore is not by nature, because by means of education, laws, and punishments we do seek to alter that. Sin comes through defect in the moral purpose (προαίρεσις). Our first parents fell through indolence of moral purpose (ῥ‹θυμία) and this is the principal cause of sin now. They marked out a path which has been trodden ever since: the force of will has been weakened in all their posterity: so that though evil is not an inherent part of man’s nature yet he is readily inclined to it (ὀξυρῥεπὴς πρὸς κακι€ν); and this tendency must be perpetually counteracted by vigorous exertion, and a bracing up of the moral purpose, with the aid of divine grace. Profoundly convinced therefore on the one hand of a strong and universal tendency to sin, but on the other of an essential freedom of the will, Chrysostom sounds alternately the note of warning and encouragement,—warning against that weakness, indolence, languor of moral purpose which occasions a fall,—encouragement to use to the full all the powers with which man is gifted, in reliance on God’s forbearance and love, and on His willingness to help those who do not despair of themselves. Despair is the devil’s most potent instrument for effecting the ruin of man; for it is that which prevents him from rising again after he has fallen. St. Paul repented, and, not despairing, became equal to angels: Judas repenting, but despairing, rushed into perdition.