Verse 6. Thou wilt prolong the king's life; or, better, "days to the days of the King thou wilt add." Death threatened, but God preserved his beloved. David, considering his many perils, enjoyed a long and prosperous reign.
And his years as many generations. He lived to see generation after generation personally; in his descendants he lived as king through a very long period; his dynasty continued for many generations; and in Christ Jesus, his seed and son, spiritually David reigns on evermore. Thus he who began at the foot of the rock, half drowned, and almost dead, is here led to the summit, and sings as a priest abiding in the tabernacle, a king ruling with God for ever, and a prophet foretelling good things to come. ( Psalms 61:7 .) See the uplifting power of faith and prayer. None so low but they may yet be set on high.
EXPLANATORY NOTES AND QUAINT SAYINGS
Verse 6. Thou wilt prolong the king's life, etc. 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 on 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. John Calvin.
Verse 6. The king's life: and his years. David speaks designedly of the days of the king instead of his own days, as might have been expected from what had been said, for the purpose of showing that he considered the promise of eternal dominion as relating not to himself personally, but to his family -- the royal family of David. E. W. Hengstenberg.
HINTS FOR PASTORS AND LAYPERSONS
Verse 6. Our King, his eternal existence, our personal joy in this, and our joy for our descendants.