2 Samuel 4:8

And they brought the head of Ishbosheth unto David to Hebron, and said to the king, Behold the head of Ishbosheth, the son of Saul, thine enemy, which sought thy life; and the Lord hath avenged my lord the king this day of Saul and of his seed. To their crime of cold-blooded assassination they added that of blasphemy by ascribing the success of their deed to Jehovah. The object of the murderers evidently was to commend themselves to David and to obtain a reward of some kind. It is impossible to correct a wrong by committing a wrong, for the punishment of all crimes is in the hands of the authorities, who have received their power from God.