Bible Verses About Purification: Washing hands in water, symbolic of innocency

All the elders of that city, who are nearest to the slain man, shall wash their hands over the heifer whose neck was broken in the valley.

I will wash my hands in innocence, so I will go about your altar, LORD;

So when Pilate saw that nothing was being gained, but rather that a disturbance was starting, he took water, and washed his hands before the multitude, saying, “I am innocent of the blood of this righteous person. You see to it.”