Deuteronomy 19 is structured to draw a heavy parallel between murder and false witness.
But if anyone hates his neighbor and lies in wait for him and attacks him and strikes him fatally so that he dies (11)
If a malicious witness arises to accuse a person of wrongdoing (16)
and he flees into one of these cities, then the elders of his city shall send and take him from there (11,12)
then both parties to the dispute shall appear before the Lord, before the priests and the judges who are in office in those days. The judges shall inquire diligently (17,18)
and hand him over to the avenger of blood, so that he may die. (12)
then you shall do to him as he had meant to do to his brother. (19)
Your eye shall not pity him (13)
Your eye shall not pity. It shall be life for life, eye for eye, tooth for tooth, hand for hand, foot for foot. (21)
but you shall purge the guilt of innocent blood from Israel, so that it may be well with you. (13)
So you shall purge the evil from your midst. And the rest shall hear and fear, and shall never again commit any such evil among you. (19, 20)
Bearing false witness against a brother is as murder. It creates a wall of division – an excommunication – between the accuser and the accused. The liar cuts off his brother. It is an attempt to cast the brother into isolation, into the outer darkness. But the judgment of God turns the lying murderer’s words against him. He is the one that is cast out without pity. Jesus recapitulates in Matthew 5:
You have heard that it was said to those of old, ‘You shall not murder; and whoever murders will be liable to judgment.’ But I say to you that everyone who is angry with his brother will be liable to judgment; whoever insults his brother will be liable to the council; and whoever says, ‘You fool!’ will be liable to the hell of fire.
It is interesting that in the middle of the passage in Deuteronomy is a statute about moving land boundary markers:
You shall not move your neighbor’s landmark, which the men of old have set, in the inheritance that you will hold in the land that the LORD your God is giving you to possess.
This is a combination of false witness and murder, but for future generations. It is the cutting off of the inheritance of the neighbor’s children through deceit.