For a thousand years in thy sight - Hebrew, "In thy eyes;" that is, It so appears to thee - or, a thousand years so seem to thee, however long they may appear to man. The utmost length to which the life of man has reached - in the case of Methuselah - was nearly a thousand years Genesis 5:27; and the idea here is, that the longest human life, even if it should be lengthened out to a thousand years, would be in the sight of God, or in comparison with his years, but as a single day.

Are but as yesterday when it is past - Margin, "he hath passed them." The translation in the text, however, best expresses the sense. The reference is to a single day, when we call it to remembrance. However long it may have appeared to us when it was passing, yet when it is gone, and we look back to it, it seems short. So the longest period of human existence appears to God.

And as a watch in the night - This refers to a portion of the night - the original idea having been derived from the practice of dividing the night into portions, during which a watch was placed in a camp. These watches were, of course, relieved at intervals, and the night came to be divided, in accordance with this arrangement, into parts corresponding with these changes. Among the ancient Hebrews there were only three night-watches; the first, mentioned in Lamentations 2:19; the middle, mentioned in Judges 7:19; and the third, mentioned in Exodus 14:24; 1 Samuel 11:11. In later times - the times referred to in the New Testament - there were four such watches, after the manner of the Romans, Mark 13:35. The idea here is not that such a watch in the night would seem to pass quickly, or that it would seem short when it was gone, but that a thousand years seemed to God not only short as a day when it was past, but even as the parts of a day, or the divisions of a night when it was gone.

For a thousand years in thy sight - As if he had said, Though the resurrection of the body may be a thousand (or any indefinite number of) years distant; yet, when these are past, they are but as yesterday, or a single thatch of the night. They pass through the mind in a moment, and appear no longer in their duration than the time required by the mind to reflect them by thought. But, short as they appear to the eye of the mind, they are nothing when compared with the eternity of God! The author probably has in view also that economy of Divine justice and providence by which the life of man has been shortened from one thousand years to threescore years and ten, or fourscore.

For a thousand years in thy sight are but as yesterday,.... Which may be said to obviate the difficulty in man's return, or resurrection, from the dead, taken from the length of time in which some have continued in the grave; which vanishes, when it is observed, that in thy sight, esteem, and account of God, a thousand years are but as one day; and therefore, should a man lie in the grave six or seven thousand years, it would be but as so many days with God; wherefore, if the resurrection is not incredible, as it is not, length of time can be no objection to it. Just in the same manner is this phrase used by the Apostle Peter, and who is thought to refer to this passage, to remove an objection against the second coming of Christ, taken from the continuance of things as they had been from the beginning, and from the time of the promise of it: see 2 Peter 3:4, though the words aptly express the disproportion there is between the eternal God and mortal man; for, was he to live a thousand years, which no man ever did, yet this would be as yesterday with God, with whom eternity itself is but a day, Isaiah 43:13, man is but of yesterday, that has lived the longest; and were he to live a thousand years, and that twice told, it would be but "as yesterday when it is past"; though it may seem a long time to come, yet when it is gone it is as nothing, and can never be fetched back again:

and as a watch in the night; which was divided sometimes into three, and sometimes into four parts, and so consisted but of three or four hours; and which, being in the night, is spent in sleep; so that, when a man wakes, it is but as a moment with him; so short is human life, even the longest, in the account of God; See Gill on Matthew 14:25.

{e} For a thousand years in thy sight are but as yesterday when it is past, and as a watch in the night.

(e) Though man thinks his life is long, which is indeed most short, yet though it were a thousand years, yet in God's sight it is as nothing, and as the watch that lasts only three hours.

90:4 Past - Indeed time seems long when it is to come, but when it is past, very short and contemptible. A watch - Which lasted but three or four hours.

when...: or, when he hath passed them

4. Even were our days now a thousand years, as Adam's, our life would be but a moment in God's sight (2Pe 3:8).

a watch-or, third part of a night (compare Ex 14:24).

90:1-6 It is supposed that this psalm refers to the sentence passed on Israel in the wilderness, Nu 14. The favour and protection of God are the only sure rest and comfort of the soul in this evil world. Christ Jesus is the refuge and dwelling-place to which we may repair. We are dying creatures, all our comforts in the world are dying comforts, but God is an ever-living God, and believers find him so. When God, by sickness, or other afflictions, turns men to destruction, he thereby calls men to return unto him to repent of their sins, and live a new life. A thousand years are nothing to God's eternity: between a minute and a million of years there is some proportion; between time and eternity there is none. All the events of a thousand years, whether past or to come, are more present to the Eternal Mind, than what was done in the last hour is to us. And in the resurrection, the body and soul shall both return and be united again. Time passes unobserved by us, as with men asleep; and when it is past, it is as nothing. It is a short and quickly-passing life, as the waters of a flood. Man does but flourish as the grass, which, when the winter of old age comes, will wither; but he may be mown down by disease or disaster.