"I have commited a sin" joke

One day a burnette goes to a preacher and says, "I have commited a sin."
Preacher: what was it.
Burnette: I stabbed a man to death.
Preacher: go drink some holy water and your sins will be forgiven.
Later a redhead goes to the preacher and says, "I have commited a sin."
Preacher: what was it.
Redhead: I pushed a man of a cliff.
Preacher: go drink some holy water and your sins will be forgiven.
later a blonde goes to the preacher and says "I have commited a sin."
preacher: what was it.
blonde: I peed in the holy water that they are drinking.