Psalms 21:6

6.For thou hast set him to be blessings for ever. Some explain these words simply thus, That God had chosen David to be king, in order to pour upon him his blessings in rich abundance. But it is evident that something more is intended by this manner of speaking. It implies, that the king had such an exuberant abundance of all good things, that he might justly be regarded as a pattern of the greatness of the divine beneficence; or that, in praying, his name would be generally used to serve as an example of how the suppliant wished to be dealt with. The Jews were accustomed to speak of those being set to be a curse, who were rendered so detestable, and on whom the dreadful vengeance of God had been inflicted with such severity, that their very names served for cursing and direful imprecations. On the other hand, they were accustomed to speak of those being set to be a blessing, whose names we propose in our prayers as an example of how we desire to be blessed; as if a man for instance should say, May God graciously bestow upon thee the same favor which he vouchsafed to his servant David! I do not reject this interpretation, but I am satisfied with the other, which views the words as implying that the king, abounding in all kind of good things, was an illustrious pattern of the liberality of God. We must carefully mark what is said immediately after concerning joy: Thou hast gladdened him with joy before thy countenance (484) The people not only mean that God did good to the king, seeing he looked upon him with a benignant and fatherly eye, but they also point out the proper cause of this joy, telling us that it proceeded from the knowledge which the king had of his being the object of the Divine favor. It would not be enough for God to take care of us, and to provide for our necessities, unless, on the other hand, he irradiated us with the light of his gracious and reconciled countenance, and made us to taste of his goodness, as we have seen in the 4th Psalm, “There be many that say, Who will show us any good? Lord, lift thou up the light of thy countenance upon us, and we shall be saved.” And without all doubt, it is true and solid happiness to experience that God is so favorable to us that we dwell as it were in his presence.