wash one's hands of something or someone

Example: “After the third argument, I washed my hands of the whole committee.”

Origin: Comes directly from the Gospel of Matthew's account of the trial of Jesus: facing pressure to have him executed despite believing him innocent, the Roman governor Pontius Pilate symbolically washes his hands before the crowd and declares, "I am innocent of the blood of this just person" (Matthew 27:24) — a physical gesture meant to publicly transfer moral responsibility for the coming execution away from himself and onto those demanding it. Shakespeare references the scene directly in Richard II (1595), writing of those who "with Pilate wash your hands," and the idiom has carried the same essential meaning ever since: a deliberate, symbolic refusal to accept any further blame or involvement in a matter, disowning responsibility the way Pilate publicly disowned his own role in Jesus's death.