19:18 inquisition. That is, a “diligent inquiry.”
19:18 a false witness. It was vitally important that the testimony of witnesses be trustworthy, particularly in view of the serious penalties (frequently even execution) specified for many crimes. The ninth of the Ten Commandments was a command not to bear false witness. Many years later, it was the testimony of false witnesses which provided an excuse for the Council to condemn Jesus to death (Matthew 26:59-61).
19:21 eye for eye. See note on Leviticus 24:20.