Here's a paraphrase of Psalm 51 that would work especially well for an Ash Wednesday service. It is written in Long Meter (LM) to the tune, MARYTON, which is common used to sing, "O Master, Let Me Walk with Thee."
Free for congregational use. Please use the following credit: "Copyright 2015, Stephen M. Fearing | www.stephenmfearing.com"
Wash me in mercy, God of love.
Cleanse me from sin with grace above.
Blot out transgression, hold me true
that I might only follow you.
I beg your pardon, God of grace;
help me to run this faithful race.
Turn me from evil, be my guide
that I may with your truth abide.
Guilty since birth this sinner’s been.
Send me your Son, my soul to win.
Purge me with hyssop, wisdom fill
my hungry heart, your path, my will.
Create in me a wholesome heart.
Send me your spirit, ne’er depart
Cast not me from your perfect peace
that righteousness will never cease.
Open my lips, that I may praise;
ever your servant, all my days.
Break and restore my solemn soul
that, through your mercy, I’ll be whole.