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SERMON IN PRINT: Cleanse Me, and I Will Be Clean

A sermon for Ash Wednesday, by Pastor Jon Zabell

Psalm 51:1-12

1 Have mercy on me, O God,

according to your unfailing love;

according to your great compassion

blot out my transgressions.

2 Wash away all my iniquity

and cleanse me from my sin.

3 For I know my transgressions,

and my sin is always before me.

4 Against you, you only, have I sinned

and done what is evil in your sight;

so you are right in your verdict

and justified when you judge.

5 Surely I was sinful at birth,

sinful from the time my mother conceived me.

6 Yet you desired faithfulness even in the womb;

you taught me wisdom in that secret place.

7 Cleanse me with hyssop, and I will be clean;

wash me, and I will be whiter than snow.

8 Let me hear joy and gladness;

let the bones you have crushed rejoice.

9 Hide your face from my sins

and blot out all my iniquity.

10 Create in me a pure heart, O God,

and renew a steadfast spirit within me.

11 Do not cast me from your presence

or take your Holy Spirit from me.

12 Restore to me the joy of your salvation

and grant me a willing spirit, to sustain me.

Dear Fellow Sinners, Cleansed by the Blood of Christ,

King David couldn’t hide his sin anymore. His adultery with Bathsheba, his murder of her husband: he’d been keeping a dirty secret. But in comes the prophet Nathan, sent from God. Nathan casually invites David to consider what should happen to a wealthy man who stole a poor man’s dearest treasure. David is angry: “He deserves to die.” Nathan hangs David by David’s own words. He says to David: You are the man! (2 Samuel 12).

What’s it like to be caught? The door is closed. No one is supposed to know. Someone walks in, and you have no way to defend what you’ve done. Or perhaps you don’t get caught until later. You keep your mouth shut, but word leaks out, and your past catches up with you. It can be devastating. Some might say that such a moment has ruined their life.

King David would not have said that about Nathan’s visit. We know exactly what David thought about being caught, because it’s recorded in Psalm 51, today’s sermon text. Before we dig in, it is interesting to note that the prophet who confronted David was named Nathan. In Hebrew, nathan means gift. Nathan’s words to David were a gift from God. Let God’s Word in Psalm 51 be your nathan today.

1. Plea (1-2)

We need that gift. We all have dirt on our record. Some of it makes us squirm. Some of it should make us squirm. Some of it we aren’t even aware of.

What should we do about it? There are people who would say we should just move on. Put the past behind you. That’s like looking at your car when it’s all caked in mud, and fixing the problem by just imagining that it’s clean.

David takes an entirely different approach. Since sin is dirt, impurity, you can’t just imagine you are clean and expect the sin to disappear. Dirt needs to be washed away. This dirt, this sin is in a place he can’t reach. He turns to God for help. He cries out: Have mercy…! Blot out…! Wash away…! Cleanse..!

Notice how helpless David’s situation is. He might have suggested that he deserved God’s help, at least a little bit. He might have said: “Forgive me, Lord: I’ve never done this before. I promise never to do it again. Can’t you see how sorry I am?” David knew better. There was nothing good in him. David was completely helpless. LORD, cleanse me!

It’s not easy for us to think of ourselves as helpless. It’s humbling. Even in everyday life, it offends our sense of dignity to have to let ourselves be cleaned by someone else. They have to see our dirt. We have to depend on them. Such things are distasteful to us. We’ll allow it, but only if we have no other choice. When it comes to our sin, it’s worse. Our sinful flesh howls in protest: I don’t need help!

But there’s no room here for dignity, and there’s no place for pride. We need to be cleansed or we die, and only God can do it.

My fellow sinners, let David’s plea for mercy in verse 1-2 remind you today of how sinful we are, and how helpless we are to fix it. Let his prayer be your prayer, too: “Have mercy on me, O God, according to your unfailing love; according to your great compassion blot out my transgressions.”

Then, together with David, let’s take stock of just how much sin we need God to forgive.

2. Dirt (3-6)

He says, “I know my transgressions, and my sin is always before me.” And he does know. The word David uses for his transgressions here is a word that in his native language carries the meaning of rebellion.

Then he takes out a measuring stick and in verses 3-6 he takes stock of the seriousness of his sins. One way to measure the seriousness of a sin is to use popular opinion. If what we do will bother or offend others, we’ll try not to do it. But if other people are o.k. with what we’re doing, then we’re o.k. with it, too. Another way to measure the seriousness of sin is to consider how it will make us feel. If it’s going to make us feel bad about ourselves later to the point that it’s hard to live with ourselves, we’ll try not to do it. But if we can deal with our feelings of guilt, maybe the sin we’re thinking about isn’t really so bad. David uses a different standard of measurement: not popular opinion, not conscience. He holds his sin up to God’s Word and measures it there. He measures his sin against the holiness of God. Then he reports his findings. He says to the Lord, “Against you, you only have I sinned.”

Fellow sinners, so it is with you and me. Even if we set aside for the moment those sins where we hurt or bother or offend someone - there are certainly plenty of those, too - but even then, how do we measure up to God’s law? How many times have we carried a grudge, something Jesus calls murder in the heart? How many times have we entertained lustful thoughts, something Jesus calls adultery in the heart? How many times have we been discontented with our lot, our calling in life? How many times have we given in to greed, to coveting? Even when nobody has gotten hurt, each of us has sinned against God too many times to count!

But is it really our fault? We hear of people everywhere defending their sins by saying, this is just the way I am. At first it may sound like David is joining his voice to that same chorus. He says, “Surely I was sinful at birth.” Is he writing off his adultery and murder? Is he claiming that’s just the way he is? No, just the opposite. David is confessing that his rebellion traces back to the first moment of his existence. You and I have to confess the same thing: “Surely I was sinful at birth, sinful from the time my mother conceived me.” So, as David says, God is right in his verdict, and he is justified when he judges us.

Only God can help us.

3. Purity (7-9)

“Cleanse me with hyssop, and I will be clean,” says David. David is pointing us to the Passover, when God rescued his people from their Egyptian slave masters. All who painted a lamb’s blood on the frame of their front door were spared. While the Egyptians mourned and grieved, God’s people quickly left to go to a land God would show them. The blood saved them. And what do you suppose the people used to paint lamb’s blood on their door frames? Their paint brush was a branch from a hyssop tree. “Cleanse me with hyssop,” says David. He’s talking about blood. Not just the blood of Passover lambs, but the blood of the Lamb of God, who takes away the sin of the world.

“Wash me,” says David, “and I will be whiter than snow.” Last I checked, blood doesn’t make things clean. This blood does. This is the holy, innocent blood of God’s Son. This blood is the price he paid to take your sin and guilt away, and that’s just what he’s done. He has taken away every last bit of sin’s stain, even the sin that is in your inmost place. He has declared you clean and holy, through and through, now and always. With this blood, God has made you whiter than snow.

We never get tired of hearing this. We’re like children at bedtime, who want their favorite story read again and again and again. Tell me again, we say. Let me hear it again. The blood of Jesus cleanses me of all my sin!

And God never gets tired of telling us. That was the main point of Nathan’s visit. Not just to say to David, “You are the man,” but to say, “The Lord has taken away your sin.” God says this same thing to us over and over, in a variety of ways. Our baptism is a daily crushing of our bones in repentance, and a daily rejoicing in God’s cleansing bath of forgiveness. The cup of wine we receive in Communion is a regular participation in the blood of God’s Lamb. And every piece of good news we hear from the Bible is like another visit from the prophet Nathan: “The Lord has taken away your sin.”

4. Joy (10-12)

It doesn’t stop with being cleansed. When God washes us of all our sin with the blood of his Lamb and creates in us a pure heart, then he also establishes a steadfast and willing spirit within us, an attitude that is eager to carry out God’s will for us in life. He restores the joy of salvation in us, joy we couldn’t have found without him, joy that can keep shining in good times and in bad times, because it is grounded in God who created and saved us.

“Do not cast me away from your presence,” says David. Our sin drives us far from God, but with his forgiveness, God holds us close to him now and forever. Let the world dish out the worst it can. Let the suffering of this life take everything you cherish away from you. God is holding you close and nothing can compare to that. Even in death he will hold on, and take you to be with him forever.

David’s words in verses 10-12 are bold words. Give me a pure heart. Give me joy. Considering what David did, how could he make such bold requests of God? But David’s boldness is not sinful. This is his faith talking. God has forgiven him and he knows it. God wants just this same kind of boldness from you, his child. Though you are full of sin, he wants you to pray. And he wants you to pray big. He doesn’t want you to settle for earthly blessings like food and home and health and physical safety. Make no mistake, those are wonderful gifts, too, from our gracious God. But they can’t compare to the grace of God in Jesus. God’s Son has shed his blood for you. You are God’s child. So be bold! You can bring your sin to God, all of it, and count on his forgiveness. You can pray boldly for joy, and for a willing and steadfast spirit, knowing that he will hear and answer.

What a dramatic moment it was when Nathan confronted David with his sin! A moment like that is coming for us all, when we meet God face to face. When that day comes, every last sin will be laid bare before God. There was only one hope for David, just as there is only one hope for you and for me. But it’s a certain hope. “Cleanse me with hyssop, and I will be clean,” said David. The blood of Jesus Christ purifies us from all sin. Friends, you’ve been cleansed, and you are clean, too, now and forever. In the name of Jesus, Amen.


NIV (c) 2011, Biblia Inc.

Sermon Copyright (c) 2022, St. Paul Lutheran Church, Green Bay, WI 54301

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