The days of our years are threescore years and ten / or even by reason of strength fourscore years
Yet is their pride but labor and sorrow / for it is soon gone, and we fly away.
Who knoweth the power of thine anger / and thy wrath according to the fear that is due unto thee?
So teach us to number our days / that we may get us a heart of wisdom (Psalm 90:10-12).
Moses is trying to do a lot more than just to provide us with a baseline about the average lifespan.
Psalm 90 is the only psalm attributed to Moses; it is a tefillah, a prayer or perhaps prayer-hymn, and the Psalter has placed it at the beginning of the fourth book of psalms (Psalms 90-106). Moses praises God as the dwelling place of His people throughout all generations (Psalm 90:1). He speaks of God’s eternal nature, existing before the mountains and the world, everlasting to everlasting (Psalm 90:2). God who created man also sees his end, returning to dust, for to God a thousand years is as a day when it is past or a watch in the night, a time passed in sleep by most and thus barely perceptible (a four hour period; Psalm 90:3-4, cf. 2 Peter 3:8). In comparison humans are like sleep or grass in the field, alive one morning, cut down by evening (Psalm 90:5-6). The people of God are consumed in God’s anger, for their iniquities are set before them and they pass their days under the wrath of the hand of God (Psalm 90:7-9).
Moses then speaks of the “average” human life of seventy to eighty years (Psalm 90:10). The figures are appropriate; life expectancy these days is on average 67 for the world and closer to 80 for industrialized nations. Yes, average life expectancy was much worse during Moses’ days on account of illness, child mortality, and other factors. Medical technology has allowed modern man to increase the average life expectancy but not nearly as much if one focuses primarily on those who have already reached a level of maturity, that is, those who could hear and understand what Moses is saying in Psalm 90. All things being equal and without significant famine, plague, or war, even in Moses’ day 70 to 80 was the average upper limit to a lifespan, and has perhaps increased by a decade or so since.
Moses did not intend to provide some interesting factoid when he speaks of a lifespan of seventy or eighty years; he says their pride is labor and sorrow, it ends soon, and we fly away (Psalm 90:10). Seventy to eighty years is our lifetime, and it may seem like a lot to us; Moses just said that to God a thousand years, 12 or so times an average lifespan, is but four hours or a day (Psalm 90:4). Moses asks who can know the power of God’s anger according to the reverence due Him (Psalm 90:11). Moses gives voice to God’s people to ask God to teach us to number our days so we can obtain wisdom (Psalm 90:12); such is the real goal of this exploration of life and time.
Yet Moses speaks for God’s people in distress and would like for YHWH to return to His people and to show mercy to them, showing them covenant loyalty so they can rejoice and be glad as many days as they have been afflicted (Psalm 90:13-15). God is asked to have His work appear to His servants, His glory on their children, the favor of the Lord upon His people, establishing the work of their hands (Psalm 90:16-17). Thus ends Moses’ prayer.
We could imagine many circumstances in which Moses is speaking from experience. He led the Israelites out of Egypt after they had suffered deep distress for at least eighty years if not longer (Exodus 12:40, Deuteronomy 34:7). The people of God suffered His wrath on account of their faithless for forty years as they died in the Wilderness (Numbers 14:26-39). Yet Moses also knew that the Israelites would sin again and suffer great distress (Deuteronomy 31:27-32:44), and perhaps is giving them voice through his prayer in Psalm 90.
Israel desperately needed to keep Moses’ prayer in mind during difficult days. The Psalter is aware of this and likely places this psalm in its position as Psalm 90, the introduction to Book IV of the Psalms, but also after the maskilim of Heman and Ethan the Ezrahites (Psalms 88-89), which maintain confidence in YHWH as God of Israel, full of covenant loyalty, but who would really like to know where that covenant loyalty has gone in light of distress and exile. Of all the “lament” psalms they do not end on a note of faith; the questions are left open. In many ways Moses is left to “answer” Heman and Ethan: yes, our days may be full of woe and suffering; we may make it to 70 or 80 but those years are full of pain; but God is eternal, to Him a thousand years is like a night of sleep, and so we must number our days and be wise. God shows covenant loyalty and is faithful to His promises, but sometimes those promises take years to unfold, many more years than the average human life. From Abraham to the Conquest is about 590 years; from David to Jesus is about 950 years; from the hope of the end of exile to the establishment of Jesus’ eternal Kingdom was no less than 570 years. God was not slow as many count slowness; He was patient, and worked according to His purposes.
We also do well to keep Moses’ prayer in mind, not least because Peter quotes Psalm 90:4 in 2 Peter 3:8. It has been almost two thousand years since Jesus ascended to heaven (Acts 1:1-11); that may be 25 times the average lifespan of a human, but it is only as a half a night or two days to God. When we experience great trial and distress, living our seventy or eighty years in labor and sorrow, we may be tempted to wonder where the promise of God’s goodness or covenant loyalty has gone. We must remember that God has promised to give eternity of joy and rest, far more and longer than the days of our sorrow and pain (Romans 8:17-18, 2 Corinthians 4:17). We do well to ask for God to teach us to number our days and get wisdom, to always remember that God’s time-frame is not our time-frame, and it is for us to trust that all things will work together for good for the true people of God (Romans 8:28). May we serve God in Christ and obtain the blessing!
Ethan R. Longhenry