For a thing is useless or imperfect, if it does not fulfil what it was given for.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic useless
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

“Whether One Who Has Already Obtained Grace, Can, of Himself and Without Further Help of Grace, Do Good and Avoid Sin? Objection 1: It would seem that whoever has already obtained grace, can by himself and without further help of grace, do good and avoid sin. For a thing is useless or imperfect, if it does not fulfil what it was given for. Now grace is given to us that we may do good and keep from sin. Hence if with grace man cannot do this, it seems that grace is either useless or imperfect. Obj. 2: Further, by grace the Holy Spirit dwells in us, according to 1 Cor.” source