Proverbs 20:5

Purpose in the heart of man is deep water, but a man of understanding will draw it out.

Psalm 64:6

They search out iniquities, [saying,] We have accomplished a diligent search. And the inward part of man and the heart [are] deep.

Proverbs 18:4

The words of a man's mouth are deep waters. The wellspring of wisdom is a flowing brook.

1 Corinthians 2:11

For what man knows the things of the man, except the spirit of the man in him? And so nobody knows the things of God except the Spirit of God.

Treasury of Scripture Knowledge

Summary

Counsel in the heart of man is like deep water; but a man of understanding will draw it out.

Bible References

General references

Proverbs 18:4
The words of a man's mouth are deep waters. The wellspring of wisdom is a flowing brook.
Psalm 64:6
They search out iniquities, [saying,] We have accomplished a diligent search. And the inward part of man and the heart [are] deep.
1 Corinthians 2:11
For what man knows the things of the man, except the spirit of the man in him? And so nobody knows the things of God except the Spirit of God.