Since man's nature is dependent on a higher nature, natural knowledge does not suffice for its perfection, and some supernatural knowledge is necessary, as stated above.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic perfection supernatural
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

“that "it behooves a learner to believe." Hence in order that a man arrive at the perfect vision of heavenly happiness, he must first of all believe God, as a disciple believes the master who is teaching him. Reply Obj. 1: Since man's nature is dependent on a higher nature, natural knowledge does not suffice for its perfection, and some supernatural knowledge is necessary, as stated above. Reply Obj. 2: Just as man assents to first principles, by the natural light of his intellect, so does a virtuous man, by the habit of virtue, judge aright of things concerning that virtue; and in this way, by the light of faith which God bestows on him, a man assents to matters of faith and not to those which are against faith.” source