Sing unto the Lord with thanksgiving,.... These are the words of the psalmist unto the Israelites, according to Aben Ezra and Kimchi; but may be an exhortation to all men, especially good men; who are capable of observing the following things concerning providential goodness and special grace, on account of which they are called upon to "sing unto the Lord": or to "answer" ; to sing alternately, or by responses; the word is used for singing, Ho 2:15; see Ex 15:21; and intends vocal singing, as the next clause instrumental singing, as Kimchi observes.
However, the Lord is the object of it, to whom praise is to be sung for all the great and good things done by him, and that "with thanksgiving" to God for them; which, though a distinct thing from singing, and may be done without it, as in prayer; yet singing ought never to be without that; see Eph 5:19;sing praise upon the harp unto our God; an instrument of music used in the times of the Old Testament; an emblem of the heart, and of making melody in it to the Lord: the hearts of believers are the harps of God, on and with which they sing unto him, when they sing aright, and these are in proper tune.