The words of the mouth are deep waters, but the fountain of wisdom is a rushing stream. (NIV)
The words of a [discreet and wise] man's mouth are like deep waters [plenteous and difficult to fathom], and the fountain of skillful and godly Wisdom is like a gushing stream [sparkling, fresh, pure, and life-giving]. (AMP)
The words of a man's mouth are as deep waters, and the wellspring of wisdom as a flowing brook. (KJV)