Cross reference
Proverbs 20:5
5 Counsel in the heart of a man `is' deep water, And a man of understanding draweth it up.
Proverbs 18:4
4 Deep waters `are' the words of a man's mouth, The fountain of wisdom `is' a flowing brook.
Psalms 64:6
6 They search out perverse things, `We perfected a searching search,' And the inward part of man, and the heart `are' deep.
1 Corinthians 2:11
11 for who of men hath known the things of the man, except the spirit of the man that `is' in him? so also the things of God no one hath known, except the Spirit of God.