*Minor differences ignored. Grouped by changes, with first version listed as example.
Thou shalt add days upon days to the king etc. [1] David cannot be considered as using these words of gratulation with an exclusive reference to himself. It is true that he lived to an extreme old age, and died full of days, leaving the kingdom in a settled condition, and in the hands of his son, who succeeded him; but he did not exceed the period of one man's life, and the greater part of it was spent in continued dangers and anxieties. There can be no doubt, therefore, that the series of years, and even ages, of which he speaks, extends prospectively to the coming of Christ, it being the very condition of the kingdom, as I have often remarked, that God maintained them as one people under one head, or, when scattered, united them again. The same succession still subsists in reference to ourselves. Christ must be viewed as living in his members to the end of the world. To this Isaiah alludes, when he says, "Who shall declare his generation or age?" -- words in which he predicts that the Church would survive through all ages, notwithstanding the incessant danger of destruction to which it is exposed through the attacks of its enemies, and the many storms assailing it. So here David foretells the uninterrupted succession of the kingdom down to the time of Christ.
1 - In the Chaldee it is: "Thou shalt add days to the days of the King Messiah; his years shall be as the generation of this world, and of the world to come."
Thou wilt prolong the king's life - literally, "Days upon the days of the king thou wilt add;" that is, Thou wilt add days to those which thou hast already permitted him to live. The language does not necessarily mean that he would have a long life, but that he would still be permitted to live. He had apprehended death. He knew that his life was sought by those who were engaged with Absalom in the rebellion. At first it was uncertain what the issue would be. He had fled for his life. But now, in answer to prayer, he felt assured that his life would be preserved; that he would be permitted to return to his home and his throne; and that as king - as the sovereign of his people - he would be permitted to honor God.
And his years as many generations - Margin, as in Hebrew, generation and generation. This probably means that he would be permitted to live longer than the ordinary time of a generation; that he would live as if one generation - or as if one ordinary lifetime - were added to another, so that he would live through successive generations of men. The average life of a generation is about thirty years. David is supposed to have lived from 1085 before the Christian era to 1016 b.c., or 69 years, which would reach a third generation. This is a more natural interpretation of the passage than to suppose that he refers to an "ideal" king, or that his dynasty would continue for many generations.
Thou wilt prolong the king's life - The words are very emphatic, and can refer to no ordinary person. Literally, "Days upon days thou wilt add to the king; and his years shall be like the generations of this world, and the generations of the world to come." This is precisely the paraphrase I had given to this text before I had looked into the Chaldee Version; and to which I need add nothing, as I am persuaded no earthly king is intended: and it is Christ, as Mediator, that "shall abide before God for ever," Psalm 61:7. Neither to David, nor to any earthly sovereign, can these words be applied.
Thou wilt prolong the king's (d) life: [and] his years as many generations.
(d) This chiefly refers to Christ, who lives eternally not only in himself but also in his members.
Thou wilt prolong the King's life,.... Or "add days to the days of the King" (a). Meaning either himself, who, though his life was in danger by fighting with the Syrians and Edomites, or rather through the conspiracy of his son; yet was assured that he should yet live many years more, and especially in his posterity; and that his kingdom would be established for ever, as was promised him, 2-Samuel 7:12. Or rather the King Messiah, so the Targum: and Kimchi observes, that if this psalm respects the captivity, the King is the King Messiah: it may be understood of his life as man; who, though he died, rose again, and lives for evermore; and that, as to the glory of God the Father, so to the good of his people, for whom he makes intercession; and of the continuance of his spiritual seed, in whom he may be said to live, and his days be prolonged, Isaiah 53:10; and of the duration of his kingdom, of which there will be no end. For it is an everlasting one, as follows:
and his years as many generations; he living, and his posterity and kingdom continuing, age after age. The Targum is,
"his years as the generations of this world, and the generations of the world to, come.''
(a) "dies super dies regis adjicieo", V. L. Pagninus, Montanus, &c.
the king--himself and his royal line ending in Christ. Mercy and truth personified, as in Psalm 40:11; Psalm 57:3.
Prolong - The years of my life and reign. Thus he speaks because his kingdom was not like Saul's, but established to him and his heirs; and because Christ, his son and heir, should actually, and in his own person possess the kingdom for ever.
*More commentary available at chapter level.