(4) For ever and ever.—This is merely a term for indefinite length. (Comp. the common salutation of a king: 1Kings 1:31; Nehemiah 2:3; Daniel 3:9.) An allusion to the eternal kingdom of the Messiah is not to be forced on the passage.

Psalm 21:4. He asked life of thee — Applied to David it means, He asked only the preservation of his short and mortal life, which was often exposed to the utmost perils. And thou gavest him length of days for ever and ever — Thou gavest him a long life and reign here, and after that didst translate him to live with thee for ever. But this was far more eminently fulfilled in Christ, who asked of his Father life, or to be saved from death, (Hebrews 5:7,) though with submission to his will: but his Father, though he saw it necessary to take away his temporal life, yet instantly gave him another, and that far more noble, instead of it, even the perfect possession of an everlasting and most glorious life, both in his soul and body, at his right hand.

21:1-6 Happy the people whose king makes God's strength his confidence, and God's salvation his joy; who is pleased with all the advancements of God kingdom, and trusts God to support him in all he does for the service of it. All our blessings are blessings of goodness, and are owing, not to any merit of ours, but only to God's goodness. But when God's blessings come sooner, and prove richer than we imagine; when they are given before we prayed for them, before we were ready for them, nay, when we feared the contrary; then it may be truly said that he prevented, or went before us, with them. Nothing indeed prevented, or went before Christ, but to mankind never was any favour more preventing than our redemption by Christ. Thou hast made him to be a universal, everlasting blessing to the world, in whom the families of the earth are, and shall be blessed; and so thou hast made him exceeding glad with the countenance thou hast given to his undertaking, and to him in the prosecution of it. The Spirit of prophecy rises from what related to the king, to that which is peculiar to Christ; none other is blessed for ever, much less a blessing for ever.He asked life of thee - An expression similar to this occurs in Psalm 61:5-6, "For thou, O God, hast heard my vows;...Thou wilt prolong the king's life, and his years to many generations." The expression in both cases implies that there had been a prayer for "life," as if life were in danger. The expression itself would be applicable to a time of sickness, or to danger of any kind, and here it is used doubtless in reference to the exposure of life in going into battle, or in going forth to war. In this apprehended peril he prayed that God would defend him. He earnestly sought protection as he went forth to the perils of war.

And thou gavest it him - Thou didst hear and answer his prayer. He was saved from danger.

Even length of days forever and ever - Thou didst grant him more than he asked. He sought life for himself; thou bast not only granted that, but hast granted to him the assurance that he should live in his posterity to all generations. The idea is, that there would be an indefinite contination of his race. His posterity would occupy his throne, and there would be no end to his reign thus prolonged. Beyond all his petitions and his hopes, God bad given the assurance that his reign would be permanent and enduring. We cannot suppose that he understood this as if it were a promise made to him personally, that "he" would live and would occupy the throne forever; but the natural interpretation is that which would refer it to his posterity, and to the perpetuity of the reign of his family or descendants. A similar promise occurs elsewhere: 2 Samuel 7:13, 2 Samuel 7:16; compare the notes at Psalm 18:50. It is by no means an uncommon thing that God gives us more than we asked in our prayers. The offering of prayer is not only the means of securing the blessing which we asked, but also often of securing much more important blessings which we did not ask. If the expression were allowable it might be said that the prayer "suggested" to the divine mind the conferring of all needed blessings, or it indicates such a state of mind on the part of him who prays that God "takes occasion" to confer blessings which were not asked; as a request made by a child to a parent for a specific favor is followed not only by granting "that" favor, but by bestowing others of which the child did not think. The state of mind on the part of the child was such as to "dispose" the parent to grant much larger blessings.

4-6. (Compare 2Sa 7:13-16). The glory and blessedness of the king as head of his line, including Christ, as well as in being God's specially selected servant, exceeded that of all others. He asked only the preservation of that short and mortal life, which was oft exposed to utmost perils.

For ever and ever; either,

1. In his posterity, in whom parents are commonly said to live. Thou gavest the kingdom not only to himself for a season, as thou didst to Saul; but to him and to his seed for ever. Or rather,

2. In his person; for this giving answers to David’s asking. And the thing which David asked of God was not the kingdom, (wherein God had prevented his prayers, and granted what David durst not have presumed to ask,) but only life, or the saving and prolonging of his life, which his enemies designed to take away. Thou gavest him a long life and reign here, and after that thou didst translate him to thy heavenly kingdom, to live with thee for ever. But this was more eminently fulfilled in Christ, who asked of his Father life, or to be saved from death, Hebrews 5:7, though with submission to his will. But his Father, though he saw it fit and necessary to take away his temporal life, yet he instantly gave him another, and that far more noble, instead of it, even the perfect possession of an everlasting and most glorious life, both in his soul and body, at his right hand.

He asked life of thee, and thou gavest it him,.... Both for himself, as man, when he was about to die, that he might be raised to life again, which was granted him; and for his people, that they might live spiritually and eternally, and accordingly life is given to him for them; and he has power to give it to as many as the Father has given him, John 17:2;

even length of days for ever and ever; the life he has for himself as man is what will ever continue; he will die no more, death will have no more dominion over him; he will live for evermore, and that to make intercession for his members, Romans 6:9; and the life which is granted them at his request is an everlasting one, both as to body and soul; for though they die as other men, they shall live again in the resurrection of the just, and never die more, but shall be like the angels in heaven; and as for the second death, that shall not harm them, nor have any power over them; they will live and reign with Christ for ever.

{c} He asked life of thee, and thou gavest it him, even length of days for ever and ever.

(c) David not only obtained life, but also assurance that his posterity would reign forever.