Verse 21. - For thy word's sake; In 1 Chronicles 17:19 we read, "For thy servant's sake." The phrase seemed, perhaps, to the Chronicler difficult, but it does not mean "because of thy previous promise," for no such promise had been given, but "because thou hast now said it." Nor does it imply pre-existing merit in David, but that God had now chosen to declare his will, and what was according to his own heart. It thus makes God's own good will and pleasure the cause of the great honours bestowed upon David. Instead of these great things, the Hebrew has this great thing; that is, the lasting continuance of David's family.

7:18-29 David's prayer is full of the breathings of devout affection toward God. He had low thoughts of his own merits. All we have, must be looked upon as Divine gifts. He speaks very highly and honourably of the Lord's favours to him. Considering what the character and condition of man is, we may be amazed that God should deal with him as he does. The promise of Christ includes all; if the Lord God be ours, what more can we ask, or think of? Eph 3:20. He knows us better than we know ourselves; therefore let us be satisfied with what he has done for us. What can we say more for ourselves in our prayers, than God has said for us in his promises? David ascribes all to the free grace of God. Both the great things He had done for him, and the great things He had made known to him. All was for his word's sake, that is, for the sake of Christ the eternal Word. Many, when they go to pray, have their hearts to seek, but David's heart was found, that is, it was fixed; gathered in from its wanderings, entirely engaged to the duty, and employed in it. That prayer which is from the tongue only, will not please God; it must be found in the heart; that must be lifted up and poured out before God. He builds his faith, and hopes to speed, upon the sureness of God's promise. David prays for the performance of the promise. With God, saying and doing are not two things, as they often are with men; God will do as he hath said. The promises of God are not made to us by name, as to David, but they belong to all who believe in Jesus Christ, and plead them in his name.For thy word's sake,.... For the sake of the promise he had made to him by Samuel, that he should be king, and his kingdom should be established; or for the sake of the Messiah, that should spring from him; the Memra, as the Targum, the essential Word of God; and so the Septuagint version, "because of thy servant", with which agrees the parallel text in 1 Chronicles 17:19,

and according to thine own heart; of his own sovereign good will and pleasure, of his own grace, as the Arabic version, and not according to the merits and deserts of David:

hast thou done all these great things; in making him king of Israel, and settling the kingdom in his posterity to the times of the Messiah, who should spring from him:

to make thy servant know them; as he now did by Nathan the prophet, what he and his should enjoy for time to come; so that it is not only a blessing to have favours designed, purposed, and promised, but to have the knowledge of them, to know the things that are freely given of God.