Saint Anselm

“ Listen to the voice of strict justice; and judge according to that whether man makes to God a real satisfaction for his sin, unless, by overcoming the devil, man restore to God what he took from God in allowing himself to be conquered by the devil; so that, as by this conquest over man the devil took what belonged to God, and God was the loser, so in man's victory the devil may be despoiled, and God recover his right. ”

“ Therefore man cannot and ought not by any means to receive from God what God designed to give him, unless he return to God everything which he took from him; so that, as by man God suffered loss, by man, also, He might recover His loss. ”

“ But this cannot be effected except in this way: that, as in the fall of man all human nature was corrupted, and, as it were, tainted with sin, and God will not choose one of such a race to fill up the number in his heavenly kingdom; so, by man's victory, as many men may be justified from sin as are needed to complete the number which man was made to fill. But a sinful man can by no means do this, for a sinner cannot justify a sinner. ”