Psalm 51

Sermon: Sunday, 19th May, 2024
Speaker: John Johnstone
Scripture: Psalm 51

What is your favourite song? Sometimes we love a song for the melody and sometimes for the lyrics; the best songs are strong in both. Sometimes I wish I knew more about the background of certain songs. Why has the songwriter chosen certain phrases? What has happened to him exactly? For some of the 150 psalms we wish we could know the background. But for Psalm 51 we do not have to wonder. The title of the psalm (which is part of the psalm) tells us: ‘A psalm of David. When the prophet Nathan came to him after David had committed adultery with Bathsheba.’

1. The background of the song

We can read the account in 2 Samuel chapters 11 -12, and so we can understand exactly why King David has so much to confess. He catches sight of a married woman called Bathsheba bathing, and instead of turning his eyes away and praying for help in his temptation, he fixes his gaze and gives in to temptation, with lustful and covetous thoughts. Eventually, David abuses his power, committing adultery. In an attempt to cover up his sin (you never can!) he tries to get Uriah drunk so he thinks the child expected is his – and when that plan does not work, he has Uriah murdered. Uriah is one of the heroes of David’s army – David would have known him. He is not a faceless figure. And so, David had flouted so many of God’s commands: stealing, adultery, lying, coveting and murder.

In 1 Samuel 13:14, David is described as ‘a man after God’s own heart’. Yet, he falls so spectacularly here. What has all of this got to do with us 3000 years later?

It reminds us that all Christians are capable of falling suddenly and deeply into sin. Do you believe that? What are you capable of given the opportunity to sin? It might begin with something in the heart, like a lustful or covetous look which no one else knows about. But left unchecked, and unconfessed to God, this can grow and grow and begin to take a hold of us, leading to greater sins.

We shouldn’t look at David and say, ‘I would never do that.’ We should do the opposite. We have the seeds of all kinds of sins in our hearts. We must always be on our guard. After David murders Uriah, months go by and he seems to be oblivious to how serious his actions have been; he has no conscience about them. David is in a terrible situation: he does not realise his own sinful behaviour. Again, this has direct application to us. It is possible for us to be like that. We have wronged God in many ways. This sin acts as a barrier and we cannot have proper fellowship with God. But we do not realise it. In his grace, God sends his prophet Nathan to expose David’s sin.

Does God seem far away from you or do you feel close to God? If you feel far away, then perhaps your heart is hardened to sin- you don’t even realise how much you have offended God. ‘But your iniquities have separated you from your God; your sins have hidden his face from you, so that he will not hear.’ (Isaiah 59:2) You might be a Christian deep in sin without knowing it. You are far from God today. What hope is there for you? David was a believer far from God. He has hope for us in this Psalm. The hope is that ‘… sinners will turn back to you.’ (Psalm 51:13)

The prophet Nathan then tells the story of the rich man who steals the only lamb a poor man has: ‘David burned with anger against the man and said to Nathan, ‘As surely as the LORD lives, the man who did this deserves to die! He must pay for that lamb four times over, because he did such a thing and had no pity.’ Then Nathan said to David, ‘You are the man!’ (2 Samuel 12:5-7)

God uses his prophet and gives the simple words ‘You are the man!’ to bring David to his senses. He is finally confronted by the reality of his sin. This is a far better place for him to be. Before this, he is ignorant about how much he has offended God. However, now his soul is awakened. He wakes up to the truth about himself. Many people do not want to make this discovery about themselves.

2. Come clean

We know what it means to ‘come clean’ about something- it means to tell the truth about something which you have been keeping a secret. It is to confess something.

What a sea-change in David’s attitude. Before he was just thinking – how can I cover my tracks? But now he is thinking – how could I treat God in this way? He now sees his actions for what they are, filthy, vile behaviours which are almost beyond words.

And yet David does use words to describe them. In fact, he uses three different words for sin. It is as if he discovers new dimensions of the sin in his heart. Each graphic word he uses pictures another heinous aspect of sin.

• Transgressions : Verse 1 – David knows he is a ‘transgressor’. This word means to rebel against the known will of God (summarised in the Ten Commandments). God is the King on the throne, but David is behaving as if he is in charge of the universe. ‘I’ll murder this man so I can have more.’

God’s laws, when followed, lead to a life of love- loving God and loving our neighbours. They are like fences, preventing us from crossing the line and offending almighty God. But David crosses the line again and again. He lies, and steals and commits adultery and covets and murders. He has rebelled against God’s authority and now ‘comes clean’ about this. Friends, it’s so serious to rebel against the holy, just and righteous Creator.

We are just like David. There are many times when we deliberately choose to do things we know are wrong. There is no excuse. When we do that, we are rebelling against the King of the universe.

• Iniquity : Verse 2 – ‘Wash away my iniquity…’ Iniquity = twistedness. Why do we sin? We have a twisted heart. Augustine reflects on stealing pears from another garden- even though his own pears are better. He steals just for the sake of stealing. He sins as he loved sinning more than he loves the ways of God.

I had a compass which was broken, but I didn’t realise that. I tried to navigate in the hill, but I kept going astray. The compass wasn’t set to north as it ought to have been. Actually, our hearts are like that. Everything we think and do is just awry. We have a bias towards doing wrong. We are not good people. We are iniquitous.

• Sin : Verse 3 – ‘My sin is ever before me.’ Sin = missing the mark. We are meant to live for God and so often we live for ourselves. Think of the game of archery. We might try to please God by aiming at the bull’s eye, but the truth is that we don’t even hit the target.

Confession is more than knowing what we have done. It also means knowing who we have done it to. ‘Against you, you only, have I sinned and done what is evil in your sight.’   (Psalm 51:4) This might be surprising to you. Surely it is Uriah the Hittite David has sinned against the most. After all, he has been murdered. Well, of course, David did sin greatly against Uriah. However, David knows that the commandments he has broken are God’s commandments. The heart of the matter is this: sin is rebellion against God. God makes the rules. And all sin is an affront to Him.

I don’t think we grasp this enough in our Christian walk. If we are rude or cruel or selfish towards someone in our family, then we hurt and offend them, which is a serious business. But the most serious aspect of that behaviour is that we are simultaneously offending God in Heaven. This ought to trouble you more than the fact you have hurt those in your family. Both are significant.

In verse 4, David says: ‘Against you, you only, have I sinned and done what is evil in your sight.’   This is a sobering verse. It means that all of our sin – whether our thoughts or actions- is done before the all-seeing eyes of God! Imagine your wife was sitting beside you and could see what you were scrolling through and watching on your phone. Would that impact what you looked at? Of course, it would. Well, God is, as it were, always sitting beside you. He sees all you do, and all you think. Think about that. Practice thinking about that. We live before the face of God.

3. Become clean

How does David, filthy as he is from this catalogue of vile sin, become clean? And how can we in all our sin, with our own respective catalogues, become clean?

We must cast ourselves on the mercy of God. ‘Have mercy on me, O God.’   (Psalm 51:1) Mercy, by definition, is something that we do not deserve. ‘If you, Lord, kept a record of sins, Lord, who could stand?’   (Psalm 130:3) To be become clean, we must cry out to God for mercy. Have you done that?

It is nothing short of amazing that God does not treat us as our sins deserve. It is because of his character. God is a God of covenant-love. God has pledged that if we confess our sins to him without excuse, he will have mercy on us. ‘Whoever conceals their sins does not prosper, but the one who confesses and renounces them finds mercy.   (Proverbs 28:13) He is the God of great compassion. What a wonderful incentive this is for us to cry out to him for mercy!

Let’s focus on verse 7 for a moment: ‘Cleanse me with hyssop, and I will be clean; wash me, and I will be whiter than snow.’   What is going on here? I think that our sin is being compared to an awful skin disease, such as leprosy. We read in Leviticus, that a diseased person must leave the camp for a certain period of time. They will be examined by a priest and if healed, the priest must sacrifice a bird, and using the hyssop plant as a brush, sprinkle blood on the one to be cleansed seven times. ‘Seven times he shall sprinkle the one to be cleansed of the defiling disease, and then pronounce them clean.’   (Leviticus 14:7)

So, when David asks God to cleanse him with hyssop, he is acknowledging that his sin is like a terrible skin disease and he desperately needs God to make him clean again, through sacrifice – through someone dying in his place. We know that it is not possible for the blood of animals to take away sin see (Hebrews 10:4) and we know the amazing truth that it is the blood of Jesus which is able to cleanse us from all sin.

As we celebrate the Lord’s Supper, know this: we are in this Psalm. If we trust in the death of Jesus, then we have been cleansed with hyssop, not with the blood of a bird, but with the precious blood of Christ. This means that we are whiter than the snow in God’s eyes. Thanks be to God!

4. Restored to usefulness.

After such appalling failure, we might wonder if there was any way back for King David. Likewise, perhaps in your Christian life, you have spectacularly failed others and dishonoured and rebelled against the LORD in the process. Is there any way back for you?

What is the way back? The way back is to pray to the LORD for purity. Pray to him for a clean heart. ‘Create in me a pure heart, O God…’   (Psalm 51:10) This word ‘create’ is really important. You cannot change your own heart. You cannot create that change on your own. But God can create it.

God created the world in six days. Creating is what God does. It is miraculous. The same thing is required if backslidden Christians are going to move forward once again- we need the miracle of God creating a clean heart within us.

John Calvin: “If there is any greater exercise of power than that which brought all things out of nothing, it is that which makes a saint out of a sinner.”

The thing is – God has promised to make saints out of sinners. ‘… being confident of this, that he who began a good work in you will carry it on to completion until the day of Christ Jesus.’   (Philippians 1:6)

Let me be blunt. You might be a Christian whose heart has grown cold. You seldom pray and seldom read the Bible. Oftentimes, the way of the world seems more attractive. You might even be living a double life. What should you do? You must confess your sins to God in prayer. You must plead for mercy, based on the death of Christ. And you must ask for God’s power to create a pure heart within.

Do so with this truth ringing in your ears: ‘God can make me useful once again.’