to bubble up and gush out, as water from a spring or words from a mouth
The picture under this word is a spring. Water finds a weak place in the ground and comes up under its own pressure: nobody pumps it, and nobody easily stops it. Hebrew has a separate verb for water running down a slope, "to flow" (נָזַל); this one is for water pushing up from below. The plain physical use survives once, in Proverbs 18:4, where wise words are called a gushing stream.
The other ten times, the spring has moved into a person's mouth. Speech becomes an overflow: what has been stored inside comes up and out on its own. That is why the same verb covers speech worth hearing and speech worth fleeing:
- the sky pours out its message day after day, without a sound (Psalm 19:2)
- a teacher pours out riddles handed down from long ago (Psalm 78:2)
- lips pour out praise, and a whole congregation pours out the memory of God's goodness (Psalm 119:171, Psalm 145:7)
- enemies pour out threats while swords are on their lips (Psalm 59:7)
- a fool's mouth pours out stupidity, and the arrogant pour out boasting (Proverbs 15:2, Psalm 94:4)
The word passes no verdict of its own. Proverbs 15:28 puts the contrast plainly: the good person's heart works an answer over first, in the quiet muttering of someone turning a thought around (הָגָה), while the wicked mouth simply lets what is in it come up. Fluent, abundant, effortless speech is not wisdom. It only shows what has already been poured in.
One use stays with liquid. In Ecclesiastes 10:1 dead flies make a perfumer's oil bubble up and turn, the same welling motion applied to something spoiling rather than to something fresh.
Nuances
Whether the two halves of Proverbs 18:4 contrast two kinds of speech or stack three images of one wise speech.
- majorityThe lines run in parallel: deep waters, a gushing stream, and a fountain of wisdom are three stacked pictures of the wise person's speech, moving from hidden reserve to active flow.; Bruce K. Waltke, The Book of Proverbs: Chapters 15-31, NICOT (Eerdmans, 2005), on Prov 18:4; Michael V. Fox, Proverbs 10-31, AYB 18B (Yale University Press, 2009), on Prov 18:4; Crawford H. Toy, A Critical and Exegetical Commentary on the Book of Proverbs, ICC (T&T Clark, 1899), on Prov 18:4
- minorityThe lines stand opposed: the first names human speech as murky and hard to fathom, and the second sets against it the fresh, active stream of wisdom.; Tremper Longman III, Proverbs, Baker Commentary on the Old Testament Wisdom and Psalms (Baker Academic, 2006), on Prov 18:4