TSK · Deuteronomy 19:15

"'Whoever kills any person, the murderer shall be slain at the mouth of witnesses: but one witness shall not testify against any person that he die.

Set two men, base fellows, before him, and let them testify against him, saying, 'You cursed God and the king!' Then carry him out, and stone him to death."

But if he doesn't listen, take one or two more with you, that at the mouth of two or three witnesses every word may be established.

It's also written in your law that the testimony of two people is valid.

Don't receive an accusation against an elder, except at the word of two or three witnesses.

I will give power to my two witnesses, and they will prophesy one thousand two hundred sixty days, clothed in sackcloth."