David
Psalm 103:9ESV·traditional attribution

He will not always chide, nor will he keep his anger forever.

John Calvin Reformed @genevareformer

PSALM 103 By this psalm every godly man is taught to give thanks to God for the mercies bestowed upon himself in particular, and then for the grace which God has vouchsafed to all his chosen ones in common, by making a covenant of salvation with them in his law, that he might make them partakers of his adoption.

Commenting on Psalm 103:1-22

C.H. Spurgeon Reformed Baptist @princeofpreachers

He will not always chide. He will sometimes, for he cannot endure that his people should harbour sin in their hearts, but not for ever will he chasten them; as soon as they turn to him and forsake their evil ways he will end the quarrel.

Matthew Henry Presbyterian @wholebiblehenry

Hitherto the psalmist had only looked back upon his own experiences and thence fetched matter for praise; here he looks abroad and takes notice of his favour to others also; for in them we should rejoice and give thanks for them, all the saints being fed at a common table and sharing in the same blessings. I.

Commenting on Psalm 103:6-18