Psalm 51
Have Mercy on Me

Sermon Discussion Questions:

1. What did you learn? What encouraged and convicted you most?

2. Why do the authors of the gospels want you to think of David when describing Jesus? Why would Matthew include David's sin with Bathsheba in his David-shaped genealogy? (Matt 1:6)

3. "You will only grow in your faith to the degree you understand God's love for you, and you will only understand God's love for you to the degree you understand your own sinfulness." How does understanding your own sinfulness help better understand God's love for you?

4. How does Psalm 51 help you see your sin more clearly? How does it help you see your Savior more clearly?

5. Who are the three kinds of people addressed in the sermon? How do we arrive at the place of faith?


For to us a child is born,

to us a son is given;

and the government shall be upon his shoulder,

and his name shall be called

Wonderful Counselor, Mighty God,

Everlasting Father, Prince of Peace.

7 Of the increase of his government and of peace

there will be no end,

on the throne of David and over his kingdom,

to establish it and to uphold it

with justice and with righteousness

from this time forth and forevermore.

The zeal of the LORD of hosts will do this.

  • Isa 9:6-7


This classic prophecy from the book of Isaiah is usually recited around Christmas time because it looks forward to the long-awaited birth of the Messiah. But notice that His throne and kingdom is identified specifically as “the throne of David.” That’s an interesting detail to include alongside such august titles as: Mighty God and Prince of Peace. Remember how the angel Gabriel described the child that would be born to the virgin Mary?


“And behold, you will conceive in your womb and bear a son, and you shall call his name Jesus. He will be great and will be called the Son of the Most High. And the Lord God will give to him the throne of his father David, 33 and he will reign over the house of Jacob forever, and of his kingdom there will be no end,” (Luke 1:31-33). That sounds like an echo of Isaiah 9—a son to be born, an unending kingdom, and the throne of David. In fact, if you read the narratives of Jesus’ birth in Matthew and Luke, you’ll notice this emphasis on David all over the place (Luke 1:27, 69, 2:4, 11; Matt 1:1, 6, 17, 20; cf. Rom 1:3). And we may be read those and think: who cares? Christmas isn’t about David! Well, Matthew and Luke and Isaiah think otherwise.


In fact, here is how David-shaped the arrival of Jesus is in the gospels. If you look at the genealogy at the very beginning of Matthew’s gospel you’ll notice something interesting. After identifying Jesus as a descendant of David (Matt 1:1), Matthew creates three groups of fourteen names, tracing Jesus’ lineage back to Abraham, “17 So all the generations from Abraham to David were fourteen generations, and from David to the deportation to Babylon fourteen generations, and from the deportation to Babylon to the Christ fourteen generations,” (Matt 1:17). Now, technically speaking, these numbers are not literally correct. For Matthew to arrive at these three groups of fourteen, he has had to skip over several generations. That doesn’t mean he is lying, or the Bible is wrong—it is common to speak of any past ancestor as being a “father,” when in fact they may be a great-great-great grandfather. But that leads us to wonder: Why did Matthew do this? Why make three groups of fourteen? We use Arabic numerals to count numbers. Hebrews used something called gematria, where they use their own alphabet as a number system. So for us that would look like, “a = 1, b = 2, c = 3,” and so on. And do you know what number you get when you add up the Hebrew letters in David’s name? Fourteen. David, David, David. What is Matthew saying? Jesus’ lineage is David-shaped; Jesus is the ultimate, thrice repeated, perfect David. Why is it so important that Jesus be identified with David?


Could it be that David was awesome? Yes. David was the closest thing to the kind of King Jesus would be.

Could it be that God made a special covenant with David that his physical descendant would be the king forever? Yes. In 2 Samuel 7 God makes a covenant with David that he will never lack a son to sit on the throne of Israel.


But I want to suggest that there is another reason as well that the authors of the New Testament want you to think of David so much when you think of the arrival of Jesus Christ. Look at Matthew’s mention of David in the genealogy list: “…and Jesse the father of David the king. And David was the father of Solomon by the wife of Uriah,” (Matt 1:6). Notice the detail we are told about his son, Solomon: by the wife of Uriah. Even if you do not know the story of David and Bathsheba, you should at least be able to notice that David fathers a son by the wife of another man, by adultery. And the details are much worse than mere adultery. But why would Matthew include this in his David-shaped genealogy? How easy it would have been to simply say that David was the father of Solomon?


Matthew includes David’s sin in the genealogy for the same reason he wants to draw a connection between Jesus and David in his gospel. Yes, David is Israel’s great king, and so is Jesus. Yes, God promised David that he would have a descendant who would sit on the throne, and that descendant is Jesus. But also, David knew himself to be a great sinner in need of a great Savior, and that Savior is Jesus. Jesus came to save sinners like David. There may be no other figure in the whole of the Old Testament who knew their own sinfulness more clearly and more painfully than David did.


So, we are going to do something unusual with our Advent series this year. We are going to take the next four weeks to meditate on David’s most famous prayer of confession, Psalm 51. As we do so we will find that Jesus Christ, the son of David, has come to save sinners like David.


To the choirmaster. A Psalm of David, when Nathan the prophet went to him, after he had gone in to Bathsheba.

1 Have mercy on me, O God,

according to your steadfast love;

according to your abundant mercy

blot out my transgressions.

2 Wash me thoroughly from my iniquity,

and cleanse me from my sin!

3 For I know my transgressions,

and my sin is ever before me.

4 Against you, you only, have I sinned

and done what is evil in your sight,

so that you may be justified in your words

and blameless in your judgment.

5 Behold, I was brought forth in iniquity,

and in sin did my mother conceive me.

  • Ps 51:1-5


David’s Sin


The superscription to the psalm tells us: To the choirmaster. A Psalm of David, when Nathan the prophet went to him, after he had gone in to Bathsheba.


It’s the springtime, the time when kings go out to battle, but David remains at home and sends his general to go out in his stead. One day, he sees a woman bathing on her rooftop and David—a married man, himself—inquires who she is, and we find out that she is the wife of one of David’s soldiers, Uriah, a man who is currently away fighting on David’s behalf. So, David took her and forced himself upon her and lo and behold she became pregnant. The jig is up. What David thought he could do in the secret, is now unavoidably out in the open.


But David thinks he is cleverer than that. He summons Uriah home on the pretense of finding out more about the battle, but then encourages him to go home and spend some time with his wife. He is hoping that through his intimidation of Bathsheba into silence and tricking Uriah, Uriah and everyone else will assume the child is Uriah’s. But, there’s a problem: Uriah is a good man. He is so dedicated to David and his fellow soldiers that he will not go home to the comforts of his marriage bed, so he sleeps on the ground at the door of David’s house.

Surely, David will buckle under the weight of guilt, right? Nope. He gets Uriah drunk, hoping Uriah will go home. But he doesn’t. Even in a drunken stupor, Uriah has more character than David does.


Yet again, David does not repent, does not admit his wrong. So he doubles-down. If Uriah cannot be deceived, he can be deceased. He sends Uriah back to the front lines bearing a letter to be given to the commander of the army, a letter that has his own death sentence in it. And Uriah is killed in the battle, and David successfully steals Bathsheba without anyone saying otherwise.


Except, for this ominous passage at the conclusion of the story: “But the thing that David had done displeased the LORD,” (2 Sam 11:27).


Someone saw, Someone knew what happened. Time passes, enough for Bathsheba to give birth to the child. God sends the prophet Nathan to tell David his own story, clothed in a parable. When David hears it, he explodes in outrage and claims that the villain of that story, whoever he is, deserves immediate death for his sins, for his treachery. And Nathan, with thousand-pound words, says, “You are the man!” (2 Sam 12:7). And Nathan begins to enumerate everything that David thought he had successfully kept hidden in the dark.


Now, what will David do at this point? He has thrice demonstrated his willingness to lie and twist and manipulate things to try and escape the consequences of his sin, much like his predecessor Saul. But finally, in the humiliating moment of divine confrontation, David collapses into quiet confession: “I have sinned against the LORD.” And Nathan said to David, “The LORD also has put away your sin; you shall not die. 14 Nevertheless, because by this deed you have utterly scorned the LORD, the child who is born to you shall die,” (2 Sam 12:13-14).


David is done with trying to out-clever God, done trying to lie and keep up appearances. He gives up and admits, without qualification, his sin. There will still be severe consequences—his child does die, and his kingdom is never the same. And yet the Lord will put David’s sin away—though David earlier admitted that the person who had done such a thing deserved death, which he does, God will not kill David.


Now, at some point after this interaction, David dragged himself to his room, and wrote Psalm 51. And here is the pivot point of the sermon. There comes a point in your life where the shiny picture in your mind of yourself you had, is irreparably broken. You are not what you thought you were. You are not the man you thought you would be, you are not the mother you thought you would be, not the friend, not the leader, not the Christian you thought you would be.


Exhaustion gave way to temptation, temptation gave way to compromise and sin, and sin led to a deep, dark shame. And here today you are one of three people.

  1. You are still blind to the depth of your sin, convinced that you are not that bad. Any problems in your life are defensible, and any real issues can be blamed on others.
  2. You are so despairing, so aware of your own sin that you may feel like you are a piece of garbage.
  3. You know yourself to be a great sinner but know that you are loved by a great Savior.


Here is the surprising and offensive news that Christianity offers: Person number three is where we should be, but you must become person number two beforehand. If you remain person number one, the person who thinks they are not that bad, then you will never know the gentle brilliance and warm sunshine of God’s love. Not truly. It will be hidden by the dark cloud cover of your self-righteousness. “One reason some Christians remain shallow their whole lives is they do not allow themselves, ever more deeply throughout their lives, to pass through the painful corridor of honesty about who they really are,” (Dane Ortlund, Deeper, p. 42).


But if you have tried to go your own way, tried to live by your own terms and find exhaustion, not freedom; find emptiness, not fullness—if you feel like you know that you are the problem, if you have shocked yourself with the evil you’re capable of, if you feel disgusted with yourself and want to give up in despair…then be encouraged! You are now ready to experience the full embrace of God’s love for sinners, you are at the station of faith and the train of God’s love is now pulling in; you need only step on. You now are ready to actually believe that the son of David has come to save sinners like David, like you, like me.


So, my aim with the rest of this sermon is to take people who are in the number one category (blind to sin) and move them to number two (despairing of sin), and then move us all to number three, faith to receive God’s love for sinners.


What did David learn about his sin from this? What can we learn about our own sin as we meditate on this prayer of confession?


What Sin Is


Sin is Stubborn


For I know my transgressions, and my sin is ever before me. (Ps 51:3)


It has been at least nine months since David’s sin with Bathsheba, probably longer, before Nathan confronts him. Time may heal wounds, but it does not allay a guilty conscience. David’s sin has hung in front of his face like a perverse carrot on a stick. What was that period of time between the initial sin and the final confrontation like for David? Surely, as the weeks turned into months, there must have been part of David that thought he had gotten away with it. The sky didn’t fall, no calamity, no judgment. David carried on with life, carried out his duties as a king, continued in leading the nation. But at the same time, behind the façade, David was rotting inside. In another psalm, David explains that this period of his life felt like his bones were disintegrating (Ps 32:3).


Have you ever sinned and swept it under the rug and assumed that the mere passing of time would dissolve your guilt? With enough force and distraction and deception, you can make yourself almost believe that it didn’t happen. If you are getting ready to throw a nice dinner party, but just before the guests arrive you realize that in the middle of the room there is a small hole where thousands of ants are swarming, and you throw a rug over it, have you solved the problem? No. You have covered it up. And the entire party is going to be a miserable experience where you will be anxiously scanning the floor, constantly scooping up ants, hoping no one notices.


What do you need to do? Eventually you need to say: Listen everyone, my house isn’t fit for a party. I have a problem that needs some deep extermination. Which would be humiliating to do, to say. But the passing of time and the pretending that there isn’t a problem will not do anything to solve it. Sin, left to itself, does not have an expiration date.


Sin is Godward


Against you, you only, have I sinned and done what is evil in your sight. (Ps 51:4)


The anxiety of “does anyone know” is in us all because, in our heart of hearts, we know that there is Someone who sees all our sin. David may have hidden his sin from the sight of others, but he could not hide from God’s sight. And in God’s sight, what David did was evil. And through David’s humiliation he learns that his sin was not merely an interpersonal conflict with his subjects. If it were, David could have brushed it off. David’s sin with Bathsheba may seem alarming to us, but that wasn’t an uncommon practice for an ancient near eastern kings at all. David could have justified it as acceptable given his rank and status. Afterall, Uriah was a Hittite, a foreigner—who would care? But here is the unique teaching of the Bible: human beings are made in the image of God, so how we treat other people is, in some way, a picture of what we think about God. So, when I lie to my spouse, I lie to God. When I lose my temper at my children, I lose my temper at God. All sin bends upward, and so judgment crashes downward.


If your child is finger painting and gets some paint on the table, it isn’t that big of a deal. But if they pull your tax returns and birth certificates out of your file cabinet and begin finger painting on those, it is much more serious. And if they begin rubbing paint on a priceless piece of art at a gallery, like they are nothing but scratch paper? The value of the object increases the seriousness of the offense. And David sees that behind his sexual assault, his murder, his dishonesty, he has treated God like He was inconsequential, unimportant, and easily fooled. And now, here, he trembles. And so should we. All our sin—whatever it is—is a strike against the face of the Almighty.


Sin is Pervasive


Behold, I was brought forth in iniquity, and in sin did my mother conceive me. (Ps 51:5)


Here David confesses one of the most shocking things in the whole psalm. He admits that the problem didn’t begin when he saw Bathsheba bathing. He has had a crooked, sinful heart from the time he was in his mother’s womb. He isn’t saying anything slanderous about his mother, he is simply stating the basic doctrine of original sin. We come into the world with hearts that are naturally turned inward upon ourselves. But here is what is most alarming to us: David’s life is so good! When we read the story of David up to this point, it is filled with courage, faithfulness, love, humility, and generosity. And if you have a reductionistic definition of sin, you will not be able to put together David’s life of virtue and his admission that he has been iniquitous from the time of birth.


Augustine defined sin as loving anything more than God, and if that is true, then that leads us to see that sin lurks in many places that we do not immediately assume are sinful. Because of this, Augustine taught that vice can wear the clothes of virtue. David did many great things for the Lord, and yet there was still inside of him a bent craving, a twisted desire that could lurk even in the midst of David’s righteous deeds. So much so, that he justified raping a woman and killing her husband. People don’t jump from 0-100 in a minute like that. It is a slow nursing of a dark desire mingled with a heart that slowly and gradually begins to disconnect from the Lord. And pretty soon, we are doing our churchy things less out of a love for God, but more out of a love to be seen a certain way. “Consider your own life. That act of service yesterday—was it in fact, at root, a matter of creating a perception of you and your virtue? Don’t answer too quickly! The way you cheerfully greet those around you today—is it, upon further reflection, mainly fueled by what you want others to think of you?” (Dane Ortlund, Deeper, p. 41).


What do we do, then? We can do nothing until we have the scales of our eyes removed, until we see with sharp clarity the pervasiveness of our sin, the heinousness of our sin. William Beveridge, an English puritan, writing in his private diary laments:


“I cannot pray but I sin. I cannot hear or preach a sermon but I sin. I cannot give an alms or receive the sacrament but I sin. Nay, I cannot so much as confess my sins, but my very confessions are still aggravations of them. My repentance needs to be repented of, my tears need washing, and the very washing of my tears needs still to be washed over again with the blood of my Redeemer,” (William Beveridge, Private Thoughts).


Are these the thoughts of a deeply depressed, mentally unhealthy man? Tied up in the bonds of a manipulative religion that shames you into submission? No!  You will only grow as a Christian to the degree that you understand God’s love for you. And you will only understand God’s love for you to the degree you understand how deeply sinful you are.


Who God Is


Have mercy on me, O God, according to your steadfast love; according to your abundant mercy blot out my transgressions. (Ps 51:1)


David has dropped a pebble down the well of his own sinfulness, and he shudders at how long it takes before it hits the bottom. So, he cries out for God be gracious towards him, to show mercy. But, of course, David doesn’t deserve mercy! He himself admitted that the one who has done what he has done deserves to die! But notice what David doesn’t say: Have mercy on me, O God, according to the smallness of my sin…according to the understandability of my sin…according to my past virtues…or even, according to the power of my faith. No, no, no: David’s request for mercy hangs on who God is, not who David is; on what God will do, not what David has done.


So who is God? He is a God of steadfast love. What is steadfast love? It is a mixture of loyalty, faithfulness, commitment and affection and desire. God’s steadfast love is a constant, unwavering, unbreakable commitment for our good, because of His deep love for us. It is the kind of loving-commitment that goes out into the rain and changes your flat tire; who visits you in the hospital when you have nothing to offer; who bears with you when you are being selfish and rude. Our love is fickle and qualified. Here is what is natural to us: If you are not too inconvenient or obnoxious, if you are fun and enhance my life, I’ll have a relationship with you. But if you snub me, or get on my nerves, or become dull? I’ll distance myself from you. But if you flagrantly hurt me? Then we become enemies. But God isn’t like us. Long after you or I would abandon a relationship with someone like us because of the cost and the toll, God remains lovingly, unwaveringly, here.


Who is God? He is a God who is abundant in mercy, or as the book of Ephesians describes it “rich in mercy,” (Eph 2:4). David may now see the depth of his sin in a way he never has before, but that now has set him up to experience the abundant mercy of God in a way he never has before. The sins of David are abundant, but they do not outsize the immensity of God’s mercy. Our sins are the stone, His mercy the ocean it is lost in; Our sins are the ice, His mercy the blazing inferno they melt in. Our sins they are many, but His mercy is more.


And this is mercy is free to any sinner who will collapse into it today. This is who God is, a God of steadfast love and abundant mercy for sinners.


How do you work this down into your heart? How do you make this personal?


When David hears Nathan’s parable, he rightly identifies that he deserves death. But after Nathan confronts him with the reality behind the parable, David confesses his sin: “I have sinned against the LORD.” And Nathan said to David, “The LORD also has put away your sin; you shall not die. 14 Nevertheless, because by this deed you have utterly scorned the LORD, the child who is born to you shall die,” (2 Sam 12:13-14).


God takes the life of David’s son, brings that child up to heaven with Him, because David does deserve to die. You shall not die…the child who is born to you shall die. The son of David dies in David’s place. Which draws our mind to another son of David who will die for sin that He did not commit, who will suffer in the place of another. But this new son of David won’t die unconscious of what is happening to Him. No, He will grow into a man and will willingly, freely choose to lay down His life, for sinners like David. Sinners like David, like me, like you, deserve the penalty of our sins. Yet, Jesus Christ, a God full of steadfast love and abundant in mercy, the God against whom we have sinned, is willing to take our place for our sins.


For to us a child is born, to us a son is given…


For God so loved the world that He gave His only son, that whoever would believe in Him would not perish but have everlasting life.