When God changes man's will from evil to good, man does not approach with insincerity.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic insincerity evil
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/19950/pg19950-images.html

Context

“Secondly, a man is said to be baptized in Christ, in so far as he receives Christ's sacrament. And thus all put on Christ, through being configured to Him by the character, but not through being conformed to Him by grace. Reply Obj. 2: When God changes man's will from evil to good, man does not approach with insincerity. But God does not always do this. Nor is this the purpose of the sacrament, that an insincere man be made sincere; but that he who comes in sincerity, be justified. Reply Obj. 3: A man is said to be insincere who makes a show of willing what he wills not.” source