As I write this, I’m visiting my mother. On the desk in the guest bedroom is an antique case containing old greeting cards that my grandfather gave to my grandmother more than 80 years ago. These cards are carefully and affectionately preserved because they express a love that at the time felt and was very significant to Roland and Esther.

But that time is long past. There are few of us left who personally witnessed the preciousness of what this couple shared over 60 years of marriage. It won’t be long before their love will pass beyond living memory and these greeting cards will lose all personal significance and likely disappear.

And this is why I recommend that you memorize Psalm 90 this year. It’s only 17 verses long and you can commit it to memory in a week or two and recite the whole psalm in less than 2 minutes.

And the benefits you’ll reap are huge. This prayer of Moses will help you keep life — your real life, your really short life — in perspective. It will help you remember what is transient and what is eternal. It will help you live wisely.

Your Life Is Like Grass, Then Comes Eternity

We all suffer from time-confusion. We know our lives are short and yet we all find this hard to actually believe. That’s because God is eternal (Psalm 90:2), we are made in his image (Genesis 1:27), he has put eternity in our hearts (Ecclesiastes 3:11), and yet as fallen creatures he has placed us all under the judgment of our bodies returning to dust (Genesis 3:19; Psalm 90:3). So we have both transiency and eternality at work in us — a spiritual dissonance. We will die, but after this there is judgment (Hebrews 9:27) leading either to eternal life (John 3:16) or eternal destruction (2 Thessalonians 1:9).

We also suffer from significance confusion. We intrinsically know that our lives are significant. God himself makes us, and he does so after his likeness, so how could we be anything but significant (Psalm 139:13–14; Genesis 1:26)? Yet sinful pride causes us to want to measure our significance, not by God’s gracious endowment, but by other people’s admiration. Our sin natures are not satisfied by the humble, yet staggering knowledge that God made us in his image; we want people to venerate us. We are significant creatures, but we want to be significant gods.

Psalm 90:1–11 is soul medicine for our time-confusion and significance confusion. Moses reminds us what our earthly lives are really like: Grass that flourishes in the morning and fades in the evening (verses 5–6). To the Maker of such grass, it is significant. In that sense, we are more significant than we know. But we are not as significant as we think, in the sense that we most often want to think.

Live Wise

Lance Armstrong popularized the phrase “Live Strong.” That’s an inspiring motto for fallen humans who so badly want to be self-sufficient and self-determining. We want to live long and live strong. But the belief that we can really do that is a delusion.

Moses is under no such delusion. He knows that under any circumstances we won’t live long and he knows we certainly aren’t strong (Psalm 90:10). What Moses wants is to “Live Wise.” That’s why he prays, “so teach us to number our days that we may get a heart of wisdom” (Psalm 90:12). Living wise only comes from knowing who God is and who we are.

If God is eternal and our earthly lives are transient, then there is only one place the wise will choose to live: in God, our forever dwelling place (Psalm 90:1). If we are brought to an earthly end by the righteous wrath of God for our sins (Psalm 90:7–8), then there is only one thing the wise will seek during this brief terrestrial sojourn: God’s mercy and favor (Psalm 90:13, 17). And if our fleeting, grass-like lives are full of “toil and trouble” (Psalm 90:10), then there is only one satisfaction the wise will pursue: the steadfast love of the everlasting God (Psalm 90:14).

And daily numbering our days — recalling how increasingly few of them we have — is the way Moses knows will cultivate a heart of wisdom. Living wise is not resolving to increase our strength, but to increase our faith. Living wise is growing in dependence, not a growing independence.

Psalm 90 will help you live wise this year. Commit it to memory and make it part of your daily prayers. It’s a small investment that will yield you a large return. It will help you number your days, it will remind you that you are grass, it will help you trust all your toil and trouble to the providential righteous judgment of God and seek him as your refuge, and it will give you God’s words to pray for God’s mercy and for satisfaction in him alone.

Someday someone will sift through the few artifacts that remain of your life. So much of what seems so important to you now will have passed away into oblivion. Are you spending your short life on what really matters? Life is too short to waste. Live wise.