Today’s Passage: Psalm 90
This psalm closes this series’ walk through ten days on wisdom and mortality, and it does so with the only psalm in the entire collection attributed to Moses.
Context The only psalm of Moses, opening Book IV
This psalm’s heading, “a prayer of Moses the man of God,” makes it unique in the whole Psalter, the sole psalm credited to Moses himself. It also opens Book IV of the Psalter (Psalms 90-106), the very book this series already noted closing with Psalm 106’s confession of sin and hope of restoration. Fittingly, Book IV opens with Moses meditating on human frailty and closes with Israel’s long history of failure and mercy, the same honest realism carried from beginning to end.
As you read, hold this: the psalm’s entire argument rests on one contrast, God’s eternity against human brevity, and it asks for exactly one thing mortality itself can teach, if faced honestly.
Psalm 90:1-6 (BSB)
A prayer of Moses the man of God.
¹ Lord, You have been our dwelling place through all generations. ² Before the mountains were born or You brought forth the earth and the world, from everlasting to everlasting You are God. ³ You return man to dust, saying, “Return, O sons of mortals.” ⁴ For in Your sight a thousand years are but a day that passes, or a watch of the night. ⁵ You sweep them away in their sleep; they are like the new grass of the morning— ⁶ in the morning it springs up new, but by evening it fades and withers.
Study notes The same measure, applied to God's patience
Verse 4’s striking claim about time, that a thousand years pass before God like a single day, is not left in the Old Testament. Peter reaches for the identical comparison, centuries later, to explain why God’s promised return has not yet come.
"With the Lord a day is like a thousand years, and a thousand years are like a day." 2 Peter 3:8 (BSB)
Where Moses uses this measure to humble human pride, Peter uses it to explain divine patience: what looks like delay to mortal eyes is, from God’s own vantage point, no delay at all.
Psalm 90:7-11 (BSB)
⁷ For we are consumed by Your anger and terrified by Your wrath. ⁸ You have set our iniquities before You, our secret sins in the light of Your presence. ⁹ For all our days decline in Your fury; we finish our years with a sigh. ¹⁰ The length of our days is seventy years—or eighty if we are strong—yet their pride is but labor and sorrow, for they quickly pass, and we fly away. ¹¹ Who knows the power of Your anger? Your wrath matches the fear You are due.
Moses does not treat human mortality as morally neutral. He connects it directly to sin, secret sins exposed in God’s presence, a sober honesty rarely voiced so plainly elsewhere.
Psalm 90:12-17 (BSB)
¹² So teach us to number our days, that we may present a heart of wisdom. ¹³ Return, O LORD! How long will it be? Have compassion on Your servants. ¹⁴ Satisfy us in the morning with Your loving devotion, that we may sing for joy and be glad all our days. ¹⁵ Make us glad for as many days as You have afflicted us, for as many years as we have seen evil. ¹⁶ May Your work be shown to Your servants, and Your splendor to their children. ¹⁷ May the favor of the Lord our God rest upon us; establish for us the work of our hands—yes, establish the work of our hands!
Word study Number — manah (Psalm 90:12)
“Number” translates מָנָה (manah, mah-NAH) — Strong's H4487, “to count, to reckon, to assign.” The prayer is specific: not a request to live longer, but to actually count and reckon with the days already given, so that mortality itself becomes the teacher of wisdom rather than a fact quietly avoided.
The psalm’s closing request, repeated twice for emphasis, “establish the work of our hands,” asks for something lasting despite mortality, work that outlives the brief, grass-like life that produced it.
Personal Application
- Verse 12’s prayer asks God to “teach us to number our days,” turning mortality into wisdom rather than despair. Would a clearer sense of your own life’s brevity change any specific priority you are currently living by?
- The psalm’s closing request is for God to “establish the work of our hands.” Is there work in your own life you are currently doing that you would want to genuinely outlast you?
Decision of the day: Pray verse 12 word for word today, “teach us to number our days,” and let it shape one specific choice about how you spend today’s hours.
Pray to Close
The truth to carry from this psalm, and from these ten days on wisdom and mortality: our days are genuinely brief, like grass that springs up and withers within a single day. The wisdom this whole stretch has pointed toward is not despair at that fact, but a heart shaped rightly by it.
Praise: for the LORD who has been our dwelling place through all generations, from everlasting to everlasting.
Confess: any tendency to live as though your own days were not, in fact, as brief as this psalm describes.
Ask: for a heart of wisdom, taught by numbering your days rightly, and for God to establish whatever work your hands are currently doing.
Worship for Today
O God Our Help In Ages Past · Reawaken Hymns
This hymn, Isaac Watts’s own paraphrase of this exact psalm, carries its central contrast directly into song: “time, like an ever-rolling stream, bears all its sons away,” met by the same confidence Moses first prayed, that God remains our dwelling place through it all.
Listen: