Psalm 90 – Teach us to number our days

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Service recording Sunday 5th July looking at Psalms.

Watch the service — 5 July 2026

▶ Jump to the sermon (Psalm 90) — 0:50:58

Chapters

Psalm 90

New Testament Reading: Luke 21:34-35

The grass withers, the flower fades, but the word of God endures forever. This is, we believe, God’s word.

"Be on guard, so that your hearts will not be weighted down with dissipation and drunkenness and the worries of life, and that day will not come on you suddenly like a trap; for it will come upon all those who dwell on the face of all the earth."

Scripture Reading: Psalm 90

"Lord, you have been our dwelling place in all generations. Before the mountains were born, or you gave birth to the earth and the world, even from everlasting to everlasting, you are God. You turn man back into dust and say, ‘Return, O children of men.’ For a thousand years in your sight are like yesterday when it passes by, or as a watch in the night. You have swept them away like a flood; they fall asleep. In the morning they are like grass which sprouts anew; in the morning it flourishes and sprouts anew; toward evening it fades and withers away. For we have been consumed by your anger, and by your wrath we have been dismayed. You have placed our iniquities before you, our secret sins in the light of your presence. For all our days have declined in your fury; we have finished our years like a sigh. As for the days of our life, they contain seventy years, or if due to strength, eighty years; yet their pride is but labour and sorrow, for soon it is gone and we fly away. Who understands the power of your anger, and your fury, according to the fear that is due you? So teach us to number our days, that we may present to you a heart of wisdom. Do return, O Lord; how long will it be? And be sorry for your servants. O satisfy us in the morning with your loving kindness, that we may sing for joy and be glad all our days. Make us glad according to the days you have afflicted us, and the years we have seen evil. Let your work appear to your servants, and your majesty to their children. Let the favour of the Lord our God be upon us; and confirm for us the work of our hands; yes, confirm the work of our hands."

Introduction: A Word From the Farm

As you know, this is not a devotion on Ecclesiastes; it is a devotion on Psalm 90. Simply because, as I was down at the farm, praying for you all and taking time to consider my own life and my own heart before the Lord, I stumbled across Psalm 90. And as it spoke to me in a very special way, I pray that it will speak to you in a very special way today. And I thought, on the occasion of the Lord’s Supper, we should just take a little time to meditate on something a little different today.

This is a psalm of Moses. It’s the only psalm that’s attributed to Moses in the Scriptures. Most of them, as you know, were penned by King David; there are a few by Asaph, and a few others by whoever. But this is the only psalm that is attributed to that great and humble leader, Moses, who, by the power of God, led the people out of Egypt and through the desert, and ultimately, after a period of time and of testing, crossing the Jordan River into the promised land.

That being the case, I really wanted, though, just for the sake of time and for expediency, to zero down on one particular verse; and that verse is verse 12:

"So teach us to number our days, that we may get a heart of wisdom." (Psalm 90:12)

Or we could turn it around and say something like: give us wisdom, that we might number our days carefully. And the verse that we’re talking about follows after a certain meditation in Psalm 90 that Moses is having at this particular time, which caused him to write down this psalm, or song, so that it might be sung.

Moses’ Meditations Before Verse 12

The first thing that he is meditating on, of course, is the self-existence of God. We realize that in the book of Revelation, the Lord himself is called the Alpha and the Omega, the beginning and the end. Very often, if you have children and they get to a certain age, perhaps four years old, maybe five, for those philosophical children who may be a little younger, and for those more practical who might be a little older, very often their first theological question is: who made God? And those of us who are parents will have had that one. And of course, the answer is simply, no one made God, because God has always been. God is eternal. He’s the Alpha and he’s the Omega.

That’s hard for us to understand, because we are finite creatures. We had a beginning. God knitted us together in our mother’s womb, and we had a beginning at that time, where the Lord put us and his Spirit breathed in us the breath of life, and we were born. And then we go on to live a life which is temporary, just for a few years. As the psalmist says, if we’re strong, we might get seventy years, and if we’re extra strong, we might get eighty years, and that’s about it.

If you’re interested, at the moment in New Zealand, if you’re a lady, you can expect to live to about 82 or 83, and if you’re a man, just about two or three years younger than that. At one stage, a hundred years ago, it would have been a lot less. But you can see that we’re in the top end of the meditation of Moses: seventy years, he says, but if you’re strong and extra good you might get eighty. Those are averages, of course; some people are going to live a good bit longer. The Guinness Book of Records apparently recognises 88 years for the longest marriage. The wife was 17 when she married, and the husband 20, and so they were both well and truly over 100 by the time they got there. But that’s the exception, not the rule. The averages still stand.

Secondly, this is in comparison to the self-existence of God. God has always been; and that contrasts with the finite life of men. Isaiah 40:6-8 reminds us: all men are like grass, and its beauty is like a flower. The grass withers, the flower fades, when the breath of the Lord blows on it. People are just like grass and flowers. Sobering, isn’t it? But nevertheless, we have to live with that.

Thirdly, he’s meditating on the sovereign hand of God over all of creation. Again in Isaiah chapter 40 we consider this great theme, that our Lord works all things according to the plan of his own will. The Lord comes with might, and his arm rules for him; all things are worked out according to his plan, not just the big things, but the small things as well. Remember that the Lord illustrated that when he talked about the sparrows: not one of them falls that the Lord doesn’t know. And he knows every hair upon your head. He’s talking about the detail of what God knows.

And fourthly, and more sobering perhaps, he’s meditating on the righteous judgments of God on men because of our sinfulness and our sinful state. In Psalm 51:4, King David, after he has been confronted by his sin concerning his adulterous relationship with Bathsheba, prays: be gracious to me, O God, according to your loving kindness and the greatness of your compassion; blot out my iniquities. And then he goes on to admit to the Lord: so you were justified in your words, and blameless in your judgments.

The fact is that each of us here cannot claim any real form of righteousness. And even if we had a form of righteousness, I hope that we would count it as absolute rubbish for the sake of gaining the righteousness of Christ. We have to admit that all of us, like sheep, as it says in Isaiah 53, have gone astray; every one of us has turned to our own way. All have sinned and fallen short of the glory of God. And one of the great blessings we have as believers is that we can freely admit that and come to God and experience his forgiveness. We’re not here because we’re complete, or because we’re righteous. In fact, the raw material that God starts with in our hearts is very often perhaps worse than what’s out in the world. But nevertheless, God calls us to be his children, to confess our sins before him, so that we might be strengthened, changed, sanctified, and made fit citizens for a place called heaven.

You see our iniquities, verse 8 of chapter 90; Moses says, you see our iniquities, even our secret sins. One of the marvellous things about that is to remember who wrote this psalm. It’s Moses. And of all men that have ever lived, there was perhaps not a greater man than Moses. Of every other prophet, God spoke to them in different ways, like dreams, in a more shaded kind of way. But it says of the servant Moses that he saw and spoke with God face to face. That’s really said of no one else other than the Lord Jesus Christ in all of Scripture. And yet he includes himself here: you see, God, you see our iniquities. Moses, the greatest man, is admitting that he has some secret sins too. We all have those secret sins, don’t we? The ones that no one else sees, but that God and the angels observe.

The Appeal: Teach Us to Number Our Days

So we come to our verse. After such meditations, he says: teach us to number our days, that we may get a heart of wisdom. Moses appeals for wisdom in the light of God’s truth. Wisdom is mindful, for the believer, of the temporary state of things for men. We really have just a few days to live in this life.

Now I know that if you’re under 40 or 45, you don’t think much about this. But I wish that I had thought, at that age, far more about these sorts of things. Because when you get to the last quarter of your life, like I am, you get closer to realising that there are not many days left to serve the Lord and be pleasing to him. And I think about all the years that I have wasted, all the times when I have been diverted, taken the stile on the side of the way and ended up in a place called Doubting Castle, and been tortured there by Giant Despair. There have been so many times wasted when I have done that instead of staying on the way. So when you get to where I am, not too far from getting the pension, understand that you also will look back on your lives. You have the opportunity to do something now. Please do it. That’s my encouragement to you.

And then lastly in the psalm, he goes on to appeal to God to bless the works of our hands. Unless the Lord builds the house, the labourers labour in vain, he says in another psalm. Unless God shows favour to us, then all is pointless and futile, as we’re learning through the book of Ecclesiastes.

Getting Practical: Deal With the Past

I want to get deadly practical now. If this is our meditation, if this is where we’re at, teach us to number our days, give us wisdom that we might number our days carefully, what are we going to do today about it? We can break down our life from day to day. As the old song says, one day at a time, sweet Jesus. That’s all I’m asking from you: give me the strength to take every day one day at a time. Is that not good? Is that not true? And is that not based on the precepts before us?

However, if we’re going to be like that, we need first to make sure that we’ve dealt with the past. Because in my own life and understanding, sometimes what holds us up from being a blessing in our walk with the Lord from day to day, and from numbering our days, is that we’re preoccupied too much with what’s happened in the past. And so we must be like the Apostle Paul: we must press forward now, not thinking so much about what’s been in the past, but pressing forward for the glory to come, for the service of God, to love and to please God in all of our lives.

To deal with the past, we must deal with the regrets, the mistakes, the previous indiscretions, the guilt, even the time wasted up until now. For us as believers, it’s a very simple thing to say, but sometimes a very hard thing to deal with. But the great thing about our faith, the great thing about our glorious God, is that his mercies are new every morning. So first of all, we must be careful that we’re not hanging on to past mistakes, or even past things that have affected us; maybe you have committed some great sin or indiscretion, or maybe you have been sinned against by somebody else’s sin. These things can hold us up and occupy our hearts and minds far too much, because as they do, we’re not able to step forward to the next phase of our lives.

So first of all, let’s make sure that we do indeed confess our sins to the God who is faithful and just, and will forgive us our sins and cleanse us from all unrighteousness. And if it is a case that we have been sinned against, make sure that you have put it in the Lord’s hands. It may or may not have been resolved; it doesn’t matter, if it’s in the Lord’s hands. There will come a time when it will be resolved. If somebody has done something and they haven’t sought the forgiveness of the Lord, then the Lord says, vengeance is mine; he’ll deal with it, if not in this life, then in the life to come. There are a whole lot of things in our lives that we’re never going to be able to bring to conclusion, but the opportunity for us as believers is to say, Lord, here they are.

Sometimes one of the little tricks that Christian counsellors use is the idea of going home and writing down the issues, the sins, the indiscretions; write them down, find a fire, screw it up and burn it. It’s a little illustration, but sometimes that sort of thing helps. Deal with it. Give it to the Lord. Give it all to Jesus: your broken dreams, your indiscretions, your mistakes, and the mistakes that have been made against you. Trust in the Lord with all your heart; don’t rely on your own insight; in all your ways acknowledge him, and he’ll make your path straight. Put it in his hands. The older you get, the more mistakes you’re going to make, and the more you’re going to have to draw on that great fountain of blood to ensure that your sins are forgiven and that you’re made white as snow before the Lord. That’s the first thing: deal with the past.

Embrace the Present: One Day at a Time

Secondly, embrace the present. Again, one day at a time. Align the decisions you’re making today on what matters eternally, because today is but a breath. The grass withers, the flower fades, but the word of God endures forever. God endures forever. So the decisions you’re making today, what you’re going to do for the rest of today, get practical: we’ve got half a day by the time we leave here. What are you going to do that’s going to be significant for all of eternity, as opposed to something merely temporal? Whatever it is, do it for the Lord.

Be truthful in all the circumstances we find ourselves in. Actively plan, set goals, and tick them off when done. You say, I find that hard, because I get a little depressed sometimes, and some of us do. Some of us have to deal with the vicissitudes of life far more than others. Sometimes, when life is going up and down, you know there’s a whole lot of important things that you really want to do, and that the day should present opportunities. You know all of that, but there can be so many things running through your head that you can’t decide the most important thing to do. And because you can’t decide the most important thing, you end up doing nothing, and procrastinating. I’m sure that’s happened to you at one time or another.

Three Things to Do Today

Let’s get really down to it. If you had a day left, what would you do with it? Well, you’ve all got at least the rest of today. What are you going to do?

First, remember to pray for someone whom the Lord has put on your heart. Take some time, some moments, to pray for that person you work with, play with, or learn with, the person who has been put on your heart and mind. Pray for that person today.

Second, one of the most marvellous things we’ve been given in our generation is the ability to communicate quickly with one another. So not only pray for someone today, but text somebody, send someone a message or an email of encouragement today. Build one another up in the most holy faith. If they’re a Christian, encourage them; and if they’re not, send one anyway as a point of encouragement, and take the opportunity perhaps to give an invitation.

And here’s the one that’s sometimes a little harder, where we’ve got to put ourselves out: do something for someone today. That takes more effort, because we’ve got to stop thinking about ourselves and start thinking about what we can do for others. That will take sacrifice, and a heart of serving.

So remember: what can we do today to pray for someone, to encourage one another, and to do something for someone? Brothers and sisters, by this we shall glorify God. And if we are doing this, then we are being ready for when he returns, are we not?

Prayer

Let’s pray. Father, thank you for the day that you’ve given us, and for the blessing of your word. We ask, Lord, that you’d be pleased to help us make application of these words in our lives, that we would be changed and conformed to the image of the Son, Jesus Christ, our Lord and our Saviour. Amen.

The Lord’s Supper

On the night in which he was betrayed, the Lord Jesus Christ took bread and broke it, saying, this is my body, broken for you. And he said to his disciples, I have earnestly desired to share this time with you. And I can say today that I’ve earnestly desired to share this time with you, and to have fellowship with you; but perhaps more importantly, to be reminded of the fellowship that we have with Christ Jesus, our Lord and our Saviour. Take, eat, do this in remembrance of me.

In the same way, our Lord took the cup and said, this is the blood of the new covenant. Drink this, as often as you do, in remembrance of me. As the Lord assures us: fear not, for I am with you; be not dismayed, for I am your God. I will strengthen you, I will help you, I will uphold you with my victorious right hand. And as Jesus himself said, the thief comes to steal, kill, and destroy; but I came that you might have life, and have it abundantly.