But the distinction of living from lifeless faith is in respect of something pertaining to the will, i.e. charity, and not in respect of something pertaining to the intellect. Therefore living and lifeless faith are not distinct habits.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic distinction 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

“Now since faith is a perfection of the intellect, that pertains directly to faith, which pertains to the intellect. Again, what pertains to the will, does not pertain directly to faith, so as to be able to differentiate the habit of faith. But the distinction of living from lifeless faith is in respect of something pertaining to the will, i.e. charity, and not in respect of something pertaining to the intellect. Therefore living and lifeless faith are not distinct habits. Reply Obj. 1: The saying of the Apostle refers to those imperfect things from which imperfection is inseparable, for then, when the perfect comes the imperfect must needs be done away. Thus with the advent of clear vision, faith is done away, because it is essentially "of the things that appear not."” source