Cardiognosis, meaning "Knowledge of the Heart" in a metaphysical sense, is only used in Scripture as an attribute of the Deity, to God's knowledge of man's heart, never some special knowledge men have deep in their own hearts. Indeed, all knowledge, or thought, is biblically referenced as residing in "the heart," and nowhere else ("May the words of my mouth and the meditations of my heart...(Ps. 19:14)"; "As a man thinks in his heart... (Prov. 23:7)"]. The term is found twice in the NT, both times in Acts, and does not appear in the LXX.