Moses
Psalm 37:30BSB·traditional attribution

The mouth of the righteous man utters wisdom, and his tongue speaks justice.

John Calvin Reformed @genevareformer

PSALM 37 This psalm, the title of which shows it to have been composed by David, contains most profitable instruction. Since the faithful, so long as they pursue their earthly pilgrimage through life, see things strangely confused in the world, unless they assuaged their grief with the hope of a better issue, their courage would soon fail them.

Commenting on Psalm 37:1-40

C.H. Spurgeon Reformed Baptist @princeofpreachers

The mouth of the righteous speaketh wisdom. Where the whole Psalm is dedicated to a description of the different fates of the just and the wicked, it was meet to give a test by which they could be known. A man's tongue is no ill index of his character. The mouth betrays the heart.

Matthew Henry Presbyterian @wholebiblehenry

These verses are much to the same purport with the foregoing verses of this psalm, for it is a subject worthy to be dwelt upon. Observe here, I. What is required of us as the way to our happiness, which we may learn both from the characters here laid down and from the directions here given. If we would be blessed of God, 1.

Commenting on Psalm 37:21-33