Psalm 33:21
For our heart shall rejoice in him, because we have trusted in his holy name.
For our heart shall rejoice in him,.... Not in sin, nor in themselves and in their boastings, all such rejoicing is evil; but in the Lord, "in his Word"; as the Targum is, in the essential Word of God, Christ Jesus; in his person, righteousness, and salvation; and this joy is heart joy, inward joy, real joy, joy in the Holy Ghost; and is unspeakable and full of glory. This is what the psalmist calls upon the saints to do, in the beginning of the psalm; and so his end in composing it is answered;
because we have trusted in his holy name; that is, in himself, who is holy, just, and good; and so faithful to every word of promise, to every engagement of his, and therefore to be trusted in: and hence it appears that the joy before spoken of is the joy of faith.