Wherefore the act of an inferior virtue is the better and more meritorious for being commanded by a superior virtue, whose act it becomes through being commanded by it, just as the act of faith or hope is better if it be commanded by charity.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic virtue faith
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“I answer that, For three reasons it is better and more meritorious to do one and the same deed with a vow than without. First, because to vow, as stated above (A. 5) is an act of religion which is the chief of the moral virtues. Now the more excellent the virtue the better and more meritorious the deed. Wherefore the act of an inferior virtue is the better and more meritorious for being commanded by a superior virtue, whose act it becomes through being commanded by it, just as the act of faith or hope is better if it be commanded by charity. Hence the works of the other moral virtues (for instance, fasting, which is an act of abstinence; and being continent, which is an act of chastity) are better and more meritorious, if they be done in fulfilment of a vow, since thus they belong to the divine worship, being like sacrifices to God.” source