II Samuel 22:50

50 Therefore will I praise Thee, O Jehovah, among the nations, And sing praise to Thy name. 51 As He who magnifies the salvation of His king, And showeth grace to His anointed, To David, and his seed for ever. The grace which the Lord had shown to David was so great, that the praise thereof could not be restricted to the narrow limits of Israel. With the dominion of David over the nations, there spread also the knowledge, and with this the praise, of the Lord who had given him the victory. Paul was therefore perfectly justified in quoting the verse before us (Sa2 22:50) in Rom 16:9, along with Deu 32:43 and Psa 117:1, as a proof that the salvation of God was intended for the Gentiles also. The king whose salvation the Lord had magnified, was not David as an individual, but David and his seed for ever-that is to say, the royal family of David which culminated in Christ. David could thus sing praises upon the ground of the promise which he had received (Sa2 7:12-16), and which is repeated almost verbatim in the last clause of Sa2 22:51. The Chethib מגדיל is the Hiphil participle מגדּיל, according to Ps. 18:51; and the Keri מגדּול, "tower of the fulness of salvation," is a singular conjecture.

This chapter is a psalm, a psalm of praise; we find it afterwards inserted among David's psalms (Ps. 18) with some little variation. We have it here as it was first composed for his own closed and his own harp; but there we have it as it was afterwards delivered to the chief musician for the service of the church, a second edition with some amendments; for, though it was calculated primarily for David's case, yet it might indifferently serve the devotion of others, in giving thanks for their deliverances; or it was intended that his people should thus join with him in his thanksgivings, because, being a public person, his deliverances were to be accounted public blessings and called for public acknowledgments. The inspired historian, having largely related David's deliverances in this and the foregoing book, and one particularly in the close of the foregoing chapter, thought fit to record this sacred poem as a memorial of all that had been before related. Some think that David penned this psalm when he was old, upon a general review of the mercies of his life and the many wonderful preservations God had blessed him with, from first to last. We should in our praises, look as far back as we can, and not suffer time to wear out the sense of God's favours. Others think that he penned it when he was young, upon occasion of some of his first deliverances, and kept it by him for his use afterwards, and that, upon every new deliverance, his practice was to sing this song. But the book of Psalms shows that he varied as there was occasion, and confined not himself to one form. Here is, I. The title of the psalm (Sa2 22:1). II. The psalm itself, in which, with a very warm devotion and very great fluency and copiousness of expression, 1. He gives glory to God. 2. He takes comfort i…