The heart of man is perverse and unsearchable, who can know it?
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic heart
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/19950/pg19950-images.html

Context

“until the Lord come, who both will bring to light the hidden things of darkness, and will make manifest the counsels of the hearts." But this belongs exclusively to the Divine power, according to Jer. 17:9, 10: "The heart of man is perverse and unsearchable, who can know it? I am the Lord who search the heart, and prove the reins: who give to every one according to his way." Therefore judiciary power does not belong to Christ as man but as God. On the contrary, It is said” source