Solomon
Proverbs 16:21ESV·traditional attribution

The wise of heart is called discerning, and sweetness of speech increases persuasiveness.

Matthew Henry Presbyterian @wholebiblehenry

Note, 1. Those that have solid wisdom will have the credit of it; it will gain them reputation, and they shall be called prudent grave men, and a deference will be paid to their judgment. Do that which is wise and good and thou shalt have the praise of the same. 2.

John Gill Reformed Baptist @doctorgill

The wise in heart shall be called prudent,.... He that has true wisdom in the inward part; who knows his heart and the haughtiness of it; who has the fear of God in it, which is the beginning of wisdom; who is wise unto salvation, not only knows the scheme of it, but is experimentally acquainted with it; who has not head knowledge and wisdom...

Jamieson-Fausset-Brown Reformed @jfbcommentary

wise in heart--who rightly consider duty. sweetness of the lips--eloquent discourse, persuades and instructs others.