Psalms 71:22

I will also praise thee with the psaltery ,.... An instrument of music; See Gill on Psalm 33:2 ;

even thy truth, O my God ; that is, his faithfulness in fulfilling his promises, which is never suffered to fail;

unto thee will I sing with the harp ; another instrument of music; and both typical of the spiritual melody in the heart, which believers make in praising the Lord, when they sing the Lamb's new song; see Revelation 14:2 ;

O thou Holy One of Israel ; the God of Israel, that dwells among them, and sanctifies them; and who is essentially and perfectly holy in himself, and in all his ways and works; the remembrance of which occasions praise and thankfulness, Psalm 97:12 .