Psalms 51:10
Create in me a clean heart, O God,
And renew a steadfast spirit within me.

This entire Psalm is special to me. The words penned by King David after the revelation of how far he allowed sin to enter and influence his life. He committed adultery and not long after, received word of her pregnancy.
He plotted and schemed to place the blame on the husband but when that did not work, he plotted and schemed the husband’s death, which ended successfully

But success in sin is a hollow victory.

Successful in the plot, the king is free to marry the widow and claim the child as his own.
Victory through lies and deceit leaves a trail where truth will follow and eventually find you.
Confronted about his sin, David becomes angry. Yet, he has no right to direct his anger at anyone other than himself. He is guilty. He is caught. He is revealed as “the man”.
With that revelation he repents through the words of this Psalm!

Psalms 51
1 Have mercy upon me, O God,
According to Your lovingkindness;
According to the multitude of Your tender mercies,
Blot out my transgressions.
2 Wash me thoroughly from my iniquity,
And cleanse me from my sin.
3 For I acknowledge my transgressions,
And my sin is always before me.
4 Against You, You only, have I sinned,
And done this evil in Your sight—
That You may be found just when You speak,
And blameless when You judge.
5 Behold, I was brought forth in iniquity,
And in sin my mother conceived me.
6 Behold, You desire truth in the inward parts,
And in the hidden part You will make me to know wisdom.
7 Purge me with hyssop, and I shall be clean;
Wash me, and I shall be whiter than snow.
8 Make me hear joy and gladness,
That the bones You have broken may rejoice.
9 Hide Your face from my sins,
And blot out all my iniquities.
10 Create in me a clean heart, O God,
And renew a steadfast spirit within me.
11 Do not cast me away from Your presence,
And do not take Your Holy Spirit from me.
12 Restore to me the joy of Your salvation,
And uphold me by Your generous Spirit.
13 Then I will teach transgressors Your ways,
And sinners shall be converted to You.
14 Deliver me from the guilt of bloodshed, O God,
The God of my salvation,
And my tongue shall sing aloud of Your righteousness.
15 O Lord, open my lips,
And my mouth shall show forth Your praise.
16 For You do not desire sacrifice, or else I would give it;
You do not delight in burnt offering.
17 The sacrifices of God are a broken spirit,
A broken and a contrite heart—
These, O God, You will not despise.
18 Do good in Your good pleasure to Zion;
Build the walls of Jerusalem.
19 Then You shall be pleased with the sacrifices of righteousness,
With burnt offering and whole burnt offering;
Then they shall offer bulls on Your altar.