Complete Commentary on the Whole Bible, by Matthew Henry, at sacred-texts.com
The people exhorted to praise God.
The God with whom we have to do, is a God of awful majesty. The universal and absolute sovereignty of a holy God would be too terrible for us even to think of, were it not exercised by his Son from a mercy-seat; but now it is only terrible to the workers of iniquity. While his people express confidence and joy, and animate each other in serving him, let sinners submit to his authority, and accept his salvation. Jesus Christ shall subdue the Gentiles; he shall bring them as sheep into the fold, not for slaughter, but for preservation. He shall subdue their affections, and make them a willing people in the day of his power. Also it speaks of his giving them rest and settlement. Apply this spiritually; the Lord himself has undertaken to be the inheritance of his people. It shows the faith and submission of the saints. This is the language of every gracious soul, The Lord shall choose my inheritance for me; he knows what is good for me better than I do.
Praise is a duty in which we ought to be frequent and abundant. But here is a needful rule; Sing ye praises with understanding. As those that understand why and for what reasons they praise God, and what is the meaning of the service. It is not an acceptable service, if it is not a reasonable service. We are never to forget the end of Messiah's exaltation, so continually do the prophets dwell upon the conversion of the nations to the gospel of Christ. Why do we vainly fancy that we belong to him, unless the Spirit reign in our hearts by faith? Lord, is it not thy glory and delight to give repentance to Israel and remission of sins, now that thou art exalted as a Prince and a Saviour? Set up thy kingdom in our hearts. Bring into captivity every thought to the obedience of Christ. And so sweetly constrain all the powers and faculties of the souls of thy redeemed, into holy love, fear, and delight in thee, that praise with the understanding may rise from every heart, both here and for ever, to Thee, our God.