But it seems unfitting that grace should deprive man of a gift of God by coming to him, and that a gift of God should be infused into man, on account of a mortal sin.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic sin God
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“III, iii, 15] have said that living and lifeless faith are distinct habits, but that when living faith comes, lifeless faith is done away, and that, in like manner, when a man sins mortally after having living faith, a new habit of lifeless faith is infused into him by God. But it seems unfitting that grace should deprive man of a gift of God by coming to him, and that a gift of God should be infused into man, on account of a mortal sin. Consequently others [*Alexander of Hales, Sum. Theol. iii, 64] have said that living and lifeless faith are indeed distinct habits, but that, all the same, when living faith comes the habit of lifeless faith is not taken away, and that it remains together with the habit of living faith in the same subject.” source