Series: Psalms

Service: Sun AM

Type: Sermon

Speaker: Ryan Boyer

Ps. 90: Teach us to number our days

One of the first interesting details you’ll note about Ps. 90 is that the heading says, “A Prayer of Moses,” which makes this the earliest psalm in the book of Psalms.

Psalm 90 can be divided into four main sections, and if you treat each of these sections like an ongoing sentence, then that may help to remember the overall content: “God is eternal (vv. 1-2), but man is fleeting and frail (vv. 3-6) because of his sin (vv. 7-11). So (i.e. therefore), teach us to number our days (vv. 12-17).

vv. 1-2 - God is eternal…

The first part of v. 1 is the big “So what?” of this psalm, so I’ll hold off on it until the end. For now, just note the emphasis on the eternal nature of God.

vv. 3-6 - …but man is fleeting and frail…

Compared with God’s everlasting nature, humanity’s time on the earth is here and gone in an instant. The fleeting nature of man is described in five ways.

1. He returns to the dust (v. 3). This is clearly a reference the creation of mankind from the dust (Gen. 2:7) and sin’s curse to return to the dust (Gen. 3:19 ).
2. The second seems at first to be another reference to God’s eternal nature, that for him a thousand years is as a day, but especially compared with v. 10 where man’s life is 70 or 80 years the contrast is that even a good long human life is still almost nothing compared to God. Make sure to see how Peter refers to this reference in 2 Pet. 3:3ff., 8).
3. Man’s life is often swept away in a flood. Media images of a flood that has passed through are often horrifying because there is no evidence that anything was ever there before.
4. Human life is like a dream. You might remember it, but even so, it’s not tangible.
5. Finally, human life is like grass. I’m writing this in August 2025 in St. Louis, MO. My yard has had a great year. We got a lot of rain and it didn’t get hot until July. Everybody was talking about how green everything was. And then it got hot and it all turned brown and brittle. That’s like human life. It’s only there for a minute and then the sun comes out and it’s gone. (cf. Ps. 103:15-16)

vv. 7-11 - …because of our sin.

Moses claims full responsibility for this condition. It was not what God created or intended from the start. This is especially important to remember when we consider that he was leading Israel through the wilderness constantly dealing with their complaining and rebellion and consequent suffering and punishment.

The key to this section appears to be v. 8, “You are aware of our sins; you even know about our hidden sins” (NET). I have two kinds of red in this section. Our sin leads to a hard life. We “pass away” and our life ends “like a sigh” (v. 9); and it is spent in “toil” and “trouble”, and it is “soon gone” (v. 10). The other is God’s response to our sins: anger and wrath.

There’s a difficult phrase at the end of v. 11, “according to the fear of you.” The Hebrew is literally, “and like the fear your raging fury.” I’m not sure what God’s intent was here, but here are some options:

NAS95 - “according to the fear that is due you”

NET - “Your raging fury cause people to fear you”

NIV - “Your wrath is as great as the fear that is due you”

vv. 12-17 - So teach us to number our days

This last section is the “So what?” What should we do, or what is our prayer, since human life is so fleeting and frail as a result of our sin (especially compared to God’s eternal nature)?

I’ve got this section divided into three primary requests, though I would not be dogmatic about three, or four or five.

1. Teach us to number our days (v. 12). Paul says it like this, “Look carefully then how you walk, not as unwise but as wise, making the best use of the time, because the days are evil” (Eph. 5:15-16, see also Col. 4:5).
2. Have pity on us (v. 13). This seems to be the main plea, but as I said, it could be divided into others. When Moses cried out to God, “How long!” it’s a reminder that even though 1000 years is not a long time for God, it is for us. Even a day of suffering is a long time for us, so we ask God for mercy. Most English versions ask God to “Satisfy us in the morning with your steadfast love.” I prefer to render “satisfy” as “Fill us up” (NCV). The plea in v. 15 is for God to give us at least as many good days as bad days. In all this, we are asking for pity.
3. Verses 16-17 mention both God’s work and the work of our hands, “Let YOUR work be shown to your servants” and “establish the work of OUR hands.” I wrote a note in my Bible margin that says our work should be God’s work, and our prayer is for God to establish our work as we do his work.

Conclusion

Moses said that God is eternal, but man is fleeting and frail because of our sin. His plea is for us to make the most of the few days that we do have, for God’s pity, and for our work to matter as we strive to do God’s will.

I think v. 1 is a fitting conclusion to this entire reality, “Lord, you have been our dwelling place in all generations.” You can’t see this in most English versions, but there is a double personal pronoun, which is used for emphasis. The text says, Lord, you…YOU have been our dwelling place…” Young’s Literal Translation tries to bring this out in this way, “A habitation Thou—Thou hast been, To us.” What stands out to me about this is not that being WITH God is our dwelling place, but God himself is our dwelling place. This would have been especially important for the Exodus generation who not only did not have a home, but who had not had a home for hundreds of years. God was their home. This needs to be our mindset in view of life that is so often way too short and way too hard. This world is not my home, but rather God who is eternal.