Proverbs 18:4

4 Deep water is the words of the mouth of a man; and a strand floating over is the well of wisdom. (Words from a person's mouth can be like deep water/can be as deep as the water; and the well of wisdom is like a stream flowing over.)

Proverbs 18:4 Meaning and Commentary

Proverbs 18:4

The words of a man's mouth [are as] deep waters
The words of a great and mighty man; of an excellent and valuable man, as Jarchi; or of a wise man, as Aben Ezra. The doctrines which such a man has imbibed, and his heart is full of and his mouth utters, are like to "waters", pure, purifying, and refreshing; to "deep waters", which make no noise, and cannot be easily fathomed: such are the deep mysteries of grace, the wisdom of God in a mystery, spoken among them that are perfect; of which a good man makes no boast, but humbly declares; out of the abundance of his heart, his mouth speaks; [and] the wellspring of wisdom [as] a flowing brook;
there is a spring of spiritual wisdom and knowledge in him; a well of living water, springing up unto everlasting life; and from thence it flows freely and constantly; communicating itself liberally unto others, and ministering grace to the hearers, for their edification.

Proverbs 18:4 In-Context

2 A fool receiveth not the words of prudence; no but thou say those things, that be turned (over) in his heart.

3 A wicked man, when he cometh into (the) depth of sins, despiseth wholesome lore, (or discipline,) and commandment; but scandal and shame followeth him.

4 Deep water is the words of the mouth of a man; and a strand floating over is the well of wisdom. (Words from a person's mouth can be like deep water/can be as deep as the water; and the well of wisdom is like a stream flowing over.)

5 It is not good to take the person of a wicked man in doom, that thou bow away from the truth of doom. (It is not good to favour a wicked person, so that thou turn away from the truth in judgement.)

6 The lips of a fool meddle themselves with chidings; and his mouth stirreth strives. (A fool's lips mix, or mingle, themselves in with arguments; and his mouth stirreth up strife.)