Let them now that fear the Lord say - Compare Psalm 115:11. All that worship God are interested in what God has done for me. It is a manifestation of the divine character which should cheer them. They are called, therefore, to unite with the author of the psalm in praise and thanksgiving, not merely from sympathy with him, but because great truths of religion had been illustrated, in his case, which were of as much importance to them as to him.

That fear the Lord - All sincere penitents and genuine believers. See the notes on Psalm 115:9-11 (note).

Let them now that fear the Lord say, that his mercy endureth for ever. Not the proselytes to the Jewish religion only, but all that feared the Lord among all people, as Aben Ezra observes; such as fear the Lord and his goodness, and have had an experience of his grace and mercy, which has caused them to fear him; and to whom the mercy of God is great, and on whom it is from everlasting to everlasting; and therefore should speak well of it, and set their seal to it, that it abides for ever; see Psalm 103:11.