For the greater a virtue is, the further it removes man from the contrary sin, so that it withdraws man not only from that sin, but also from whatever leads to it. And thus it is evident that the greater a virtue is, the more it withdraws man also from less grievous sins: even as the more perfect health is, the more does it ward off even minor ailments.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic health virtue
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

“Wherefore the greatest sin must needs be directly opposed to the greatest virtue, as being furthest removed from it in the same genus. Secondly, the opposition of virtue to sin may be considered in respect of a certain extension of the virtue in checking sin. For the greater a virtue is, the further it removes man from the contrary sin, so that it withdraws man not only from that sin, but also from whatever leads to it. And thus it is evident that the greater a virtue is, the more it withdraws man also from less grievous sins: even as the more perfect health is, the more does it ward off even minor ailments. And in this way the less grievous sin is opposed to the greater virtue, on the part of the latter's effect. Reply Obj. 1: This argument considers the opposition which consists in restraining from sin;” source