Psalm 51 • The Biblical Definition of Repentance


“Oops I sinned, so I need to ask for forgiveness.” Is this the way it works for you? It’s really not what the Bible teaches. This Psalm of David reveals his thoughts and emotions about seeking to repent of his sin, which were actually capital crimes involving lying, adultery, murder, and enlisting the aid of others in the execution of same. It’s easy to rush through this Psalm and over-focus on some of the most quoted Scripture in the Bible. Don’t. As we examine each of David’s thoughts and actions, ask yourself, “Is this how I go about it?” You may find the answer to why some issues keep recurring in your life in spite of having brought them to the Lord many times before. You may simply be “venting” instead of “repenting”.

Read verses 1-4

Q: To what does David make his appeal? What attributes of God does he seek?

A: “...according to Your lovingkindness; according to...Your compassion...” David is seeking grace and mercy.

Q: What specifically does David want God to do?

A: “...blot out my transgressions.” It’s the language associated with something that’s been written down in a book. Using only ink in those days, to “blot” something is the method of erasing or removing an entry. David is keenly aware that sin is recorded by God for future judgment but that it’s also within God’s power as King to expunge the record and grant a pardon.

Q: David’s sins included adultery with Bathsheba and having her husband murdered to cover up his indiscretions so he could take her as his own wife. Yet to whom does David designate as the sole object of his actions?

A: “Against You, You only, I have sinned and done what is evil in Your sight.” The very definition of sin is failing to follow God’s commandments and Law. We may hurt or even involve others in our sin, but it can only be committed against God. David’s not just honest in his appeal to God but acknowledging from the outset that there is only one Source of mercy, the same Source that is directly offended by David’s actions. David therefore knows that God is “justified” and “blameless” in however He sees David as the result of his sins.

Application: In reality, sin is a personal break in our relationship with God who is personally offended at it.

Read verses 5-9

Q: Is David trying to pass on the blame in v.5, that because of man’s sinful nature he just couldn’t help himself?

A: No, it’s more along the lines that David is confessing that his nature is even still now ready to commit sin, that the problem with sin is a continuing struggle and not actually limited to these specific sins in question, and all of this has revealed to him personally his true nature. The issue for David is compounded by v.6 in that David knows God requires the struggle with sin to be resolved by embracing His truth and wisdom from the very inner self in which sin originates.

So David is really saying that he knows he is without excuse, that man knows from birth that he has trouble with sin and that God requires man to deal with it.

Q: What was the very first recorded biblical use of hyssop?

A: It was used according to God’s instructions to apply the blood of the Passover lamb around the doors of the houses of those who wanted the angel of death to pass by their household just before Israel was released by Egypt. (Exodus 12:21-22) This allowed judgment to pass them by.

Q: How is hyssop used in Old Testament Law?

  1. To signify that a leper has been cleansed of his disease. (Leviticus 14:1-9)
  2. To signify that a dwelling has been cleansed of disease. (Leviticus 14:48-57)
  3. As part of the ritual sacrifice of the red heifer that is used to produce a special water used to remove impurity and to purify things from sin or consecrate them for the Lord’s service. (Numbers 19:1-10)

David is admitting that sin has made him both impure and filthy, conditions unsuitable for the presence of God; he needs to be cleansed according to GOD’S ways—not man’s—in order to be allowed back in His presence.

Q: What is the result of purification at the hand of God?

A: “Wash me, and I shall be whiter than snow.” David is not merely apologizing, but acknowledging that only God can restore him to God’s presence, to a right relationship with Him. He is asking God to do in reality what the rituals only symbolize.

Q: How does David describe the effect of God’s having brought to David’s attention the nature of his sins?

A: “...bones which You have broken...” For David, the pain of sin—of failing God—is as real and devastating as any personal injury, and he knows that the only healing possible is from God, a pardon that would not simply ease the pain but would, like a prisoner in an electric chair that gets the last minute telephone call commuting his sentence, cause him to “hear joy and gladness”.

Q: What is different about David’s second request for God to blot out his sin in v.9 from the first request in v.1?

A: Whereas the first request is for “my transgression”—addressing the specific issues of sin at hand—the second request is for “all my iniquities”, David having now brought his entire life before God acknowledging the need for total cleansing of all sin.

Application: An occasion for addressing specific sin is really an occasion to address all of our sins and tendencies.


Do you see that the biblical process of repentance involves more than just saying, “I’m sorry”? Do you approach repentance as one who is seeking never to duplicate the issue, or one just seeking a temporary pass until the next time? What is the right attitude and process that we should undertake?


Whereas the first half of this Psalm seeks forgiveness and purification of sin, the second half seeks spiritual renewal.

Read verses 10-13

Q: Why does David want “a clean heart” and “a steadfast spirit”?

A: The biblical definition of a “clean” heart is a “pure” heart, completely rid of sin. Such a condition allows one to reside in God’s presence. Steadfastness is sought so as to make these changes to his behavior permanent, to not repeat them, to always live according to God’s ways.

Q: Why is it that David wants “the joy of Your salvation” to be restored and not just made to generally feel good or happy with life?

A: Joy for the things of this life is fleeting and only temporary during the course of this life; salvation is the work of eternity that brings joy both in the assurance of the course of this life and the one to come.

Q: Why does David ask for “a willing spirit”? Shouldn’t he ask for wisdom or love?

A: One cannot maintain purity from sin or steadfastness to His ways without being sustained by obedience that comes from a willing heart, soul, and mind. Love and wisdom are never suitable substitutes for obedience.

Q: What can we conclude from v.13 as the biblical qualifications for a teacher or evangelist or even as a witness to others?

A: They must first be living in a right, committed relationship with God themselves.

Application: Biblical “steadfastness” is seeking to make permanent changes to behavior in accordance with God’s Word and ways.

Read verses 14-17

Q: What is the nature of David’s crimes?

A: First adultery, then murder, a capital crime demanding the death penalty referred to by David as “bloodguiltiness”. Only a king can pardon a capital crime.

Q: If forgiven by God the King of Creation, why would David promise to “sing of Your righteousness”? Shouldn’t he promise to sing about God’s mercy?

A: God’s desire is to impart righteousness to the ungodly, to do for those seeking forgiveness and mercy what they could never achieve through their own merit or work. David is speaking to an even higher character trait than mercy: God’s entire work of salvation to reconcile the whole man and make him fit for God’s presence and service.

Q: There seems to be a lot of God’s Law—particularly in the first five books of the Bible—devoted to rules, regulations, and practices regarding sacrifices. Why would David say “You do not delight in sacrifice” and “You are not pleased with burnt offering”?

A: The most common misapplication of the sacrifices is the belief that the sacrifices themselves atone for or remove sin. They don’t. They are intended to be the END of the process that first begins with “a broken and a contrite heart”. Such a person recognizes not just sin within them but has the burning desire to be rid of sin permanently. The sacrifices were supposed to be a kind of public declaration that one is not just seeking to remove sin but to never engage in it again. If it doesn’t begin with a changed heart, it’s just an empty ritual with no real meaning to God.

Application: A “broken and contrite heart” does not merely recognize sin, but desires to be permanently rid of sin.

Read verses 18-19

Q: Given the context to this point, how does this closing fit in with David’s prayer for repentance and renewal?

A: This is an illustration of sanctification, the work of separating us exclusively to God, wholly devoted to Him, and living IN the world but not OF the world. Zion symbolizes all true followers gathered to serve in His city and temple, and the walls of Jerusalem represent His protection. Only if those who seek to live exclusively according to His ways are gathered together with the right heart will the offerings be presented as God really wants them—from a people wholly devoted to Him and to no other. The city then serves as an example to the rest of the world but while it’s still in the world.

Application: Personal spiritual renewal leads to corporate spiritual renewal—it is not just about us alone.