Wash me fully from mine iniquity, and cleanse me from my sin.
David prays this psalm after the prophet Nathan has confronted him and God's light has exposed his sin. Having asked God to blot out his transgressions, he now asks for something deeper — not just a record cleared, but a stain removed.
The words for sin are not interchangeable
David uses three different words for wrong in verses 1 and 2. Here is what two of them mean:
Iniquity means what is crooked, warped, twisted. God had a way for David and for us, as straight as His righteous sceptre, but David and every one of us preferred a crooked way. "All we like sheep have gone astray; we have turned—every one—to his own way." … Sin, as David used the word, means missing the mark. God set up His mark for people to aim at. Everyone who has ever entered this world is responsible to glorify God and live to His praise.
One writer sets them in order of severity:
David speaks of his transgressions in verse 1, then in verse 2 of his iniquity and his sin. Sin is the plain word. Transgression goes further, because it breaks a declared law. Iniquity goes furthest of all, and shows a will set on wickedness. Just as David, so Israel is guilty of all of these; but all mankind is just as guilty (Rom. 3:10-19). Everyone needs a thorough washing from iniquity and a cleansing from sin. All of it must go, or there is no salvation at all.
Washing goes further than pardon
Verse 1 asked God to wipe the record clean. Verse 2 asks Him to deal with what sin has done inside the man:
David did not want only forgiveness for his sins. He needed that, no doubt, but he needed more. He needed inward cleansing from the defiling power of sin itself. The apostle says, "If we confess our sins, He is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness." Cleansing from unrighteousness is more than forgiveness of our sins, and David wanted both. Both depend on confessing our sins.
Another writer names the two sides of sin:
We can look at sin in two ways: as an offence against God, or as defilement to the sinner. God has His sovereign rights and claims over all His creatures. That is what makes sin a wrong done to Him, an outrage upon His majesty and glory. Sin in this aspect needs forgiveness… But sin is also, in its very essence and nature, defiling and polluting.
Washed like a stained garment
David could not deal with the stain himself, so he asked for the kind of washing given to filthy cloth:
He cannot undo the past, and he had no way to rid himself of the deep stain in his soul. So he pleads for a thorough washing from his iniquity and a cleansing from his sin. He felt that his iniquity had defiled the very fabric of his soul and character. A launderer beats and scrubs a filthy garment to wash it, and David felt he needed washing like that. He longed to hear the word said over him that the priest said over the cleansed and healed leper, when he declared him clean from his plague.
No one else could help
David was king, with a prophet and a priest at hand, and none of it helped:
To whom could he turn for this? Not to Nathan the prophet, and not to Zadok the priest. Even with a king's power he could not lift the burden of sin off himself. His only hope was in God, and here is the gospel. The light that had exposed his sin had also shown him the very thoughts and heart of God, so he looked up in his misery and cried to God.
Why he could ask at all
You might expect his repentance and tears to be what won him a hearing:
David comes to God not on the ground of repentance, nor of his own prayers, nor of his own tears. You may repent, and it is a blessed thing if you do. You may pray, and surely it is blessed to pray. You may weep — yes, weep bitter, bitter tears — and this is well. But none of these is the ground on which forgiveness is known; none of these is the true ground of approach to God. Forgiveness does not come from Him on the ground of what we are, but on the ground of what He is.
Summary
- Crooked. "Iniquity" is the crooked path we choose instead of God's straight one. "Sin" is missing the mark God set for every person.
- Rising. The words climb: sin, then transgression against a declared law, then iniquity, a will settled on wickedness. All of it must go, or there is no salvation.
- Deeper. David asks for more than pardon. Forgiveness lifts the charge; washing deals with sin's defiling power inside him.
- Scrubbed. David pictures a launderer beating a filthy garment clean. He longs to hear over himself the word the priest said over a healed leper.
- Nowhere else. No prophet, priest or royal power could remove the stain. David's one hope was God, and he pleaded on the ground of what God is, not on what he himself felt.