But ignorance is continual in the one who is ignorant.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic ignorance
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17897/pg17897-images.html

Context

“Now ignorance is not removed by repentance, but remains in act, all its guilt being removed by repentance. Therefore ignorance is not a sin, unless perchance it be original sin. Obj. 5: Further, if ignorance be a sin, then a man will be sinning, as long as he remains in ignorance. But ignorance is continual in the one who is ignorant. Therefore a person in ignorance would be continually sinning, which is clearly false, else ignorance would be a most grievous sin. Therefore ignorance is not a sin. On the contrary, Nothing but sin deserves punishment.” source