“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.”
King James Version (KJV)
27:24 Then Pilate took water and washed his hands - This was a custom frequently used among the heathens as well as among the Jews, in token of innocency.
Mt 27:24 When Pilate saw that . . . a tumult was made. It was a dangerous time for a tumult, with more than a million Jews in Jerusalem, and probably not a thousand Roman soldiers in the castle. If one occurred, it would be reported to Rome, and he could hardly make a plausible defense to the emperor. He therefore yielded, and gave his sanction to confessed wrong, rather than endanger himself. Washed [his] hands. A symbolic act, meaning that the responsibility of the sin was upon the Jewish authorities and people instead of himself.