No one can begin a new life, unless he repent of the old.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic life beginning
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

“Now sins cannot be hallowed, for they are opposed to the effect of the sacrament, viz. grace which blots out sin. Therefore sins are not the proper matter of this sacrament. Obj. 2: Further, Augustine says in his book De Poenitentia [Cf. Serm. cccli] : "No one can begin a new life, unless he repent of the old." Now not only sins but also the penalties of the present life belong to the old life. Therefore sins are not the proper matter of Penance. Obj. 3: Further, sin is either original, mortal or venial.” source