One is the knowledge of what one ought to believe by discerning things to be believed from things not to be believed: in this way knowledge is a gift and is common to all holy persons.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic gift holy
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

“On the other hand, in God, there is a sure judgment of truth, without any discursive process, by simple intuition, as was stated in the First Part (Q. 14, A. 7) ; wherefore God's knowledge is not discursive, or argumentative, but absolute and simple, to which that knowledge is likened which is a gift of the Holy Ghost, since it is a participated likeness thereof.
Reply Obj. 2: A twofold knowledge may be had about matters of belief. One is the knowledge of what one ought to believe by discerning things to be believed from things not to be believed: in this way knowledge is a gift and is common to all holy persons. The other is a knowledge about matters of belief, whereby one knows not only what one ought to believe, but also how to make the faith known, how to induce others to believe, and confute those who deny the faith.” source