15 One witness may not make a statement against a man in relation to any sin or wrongdoing which he has done: on the word of two or three witnesses a question is to be judged. 16 If a false witness makes a statement against a man, saying that he has done wrong, 17 Then the two men, between whom the argument has taken place, are to come before the Lord, before the priests and judges who are then in power; 18 And the judges will have the question looked into with care: and if the witness is seen to be false and to have made a false statement against his brother, 19 Then do to him what it was his purpose to do to his brother: and so put away the evil from among you.
Matthew Henry's Commentary on Deuteronomy 19:15-19
Commentary on Deuteronomy 19:15-21
(Read Deuteronomy 19:15-21)
Sentence should never be passed upon the testimony of one witness alone. A false witness should suffer the same punishment which he sought to have inflicted upon the person he accused. Nor could any law be more just. Let all Christians not only be cautious in bearing witness in public, but be careful not to join in private slanders; and let all whose consciences accuse them of crime, without delay flee for refuge to the hope set before them in Jesus Christ.