s’en laver les mains

Je m'en lave les mains n!

Je m’en lave les mains !

se laver les mains – to wash one’s hands

vs.

s’en laver les mains – to not give a damn (about it), to want/have nothing to do with it.

This expression is tied to Pontius Pilate, who upon seeing a mob gathering to demand that Jesus be crucified, had the following reaction:

When Pilate saw that he could prevail nothing, but that rather a tumult was made, he took water, and washed his hands before the multitude, saying, I am innocent of the blood of this just person: see ye to it.