Proverbs 9:9 (BSB)

Instruct a wise man, and he will be wiser still; teach a righteous man, and he will increase his learning.

From Proverbs 9. Also in the ESV.

Commentary on Proverbs 9:9

• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on Proverbs 9:1-12: Wisdom is here introduced as a magnificent and munificent queen, very great and very generous; that Word of God is this Wisdom in which God makes known his goodwill towards men; God the Word is this Wisdom, to whom the Father has committed all judgment.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on Proverbs 9:9: Give instruction to a wise man,.... In the Hebrew text it is only "give to a wise man"; give him reproof, correction, chastisement, doctrine, or instruction, be it what it will, he will be the better for it. The Septuagint, Vulgate Latin, Syriac, and Arabic versions, render it, "give occasion"; to him of showing his wisdom and of improving in it: and he will be...
• Jamieson-Fausset-Brown (Reformed), Commentary Critical and Explanatory on the Whole Bible on Proverbs 9:9: The more a wise man learns, the more he loves wisdom.
• Keil & Delitzsch (Lutheran), Biblical Commentary on the Old Testament on Proverbs 9:7-9: Pro 9:7-9 In what now follows the discourse of Wisdom is continued; wherefore she directs her invitation to the simple, i.e., those who have not yet decided, and are perhaps susceptible of that which is better: 7 “He who correcteth a scorner draweth upon himself insult; And he who communicateth instruction to a scorner, it is a dishonour to him.