Deuteronomy 17:6
At the mouth of two witnesses or three witnesses shall he that is worthy of death be put to death. At the mouth of one witness he shall not be put to death.
Numbers 35:30
Whoever kills any person, the murderer shall be put to death by the mouth of witnesses. But one witness shall not testify against any person to cause him to die.
Deuteronomy 19:15
One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sins. At the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be made sure.
Matthew 18:16
But if he will not hear you, take one or two more with you, so that in the mouth of two or three witnesses every word may be established.
2 Corinthians 13:1
I am coming to you this third time. In the mouth of two or three witnesses every word shall be established.
1 Timothy 5:19
Do not receive an accusation against an elder except before two or three witnesses.
Hebrews 10:28
He who despised Moses' Law died without mercy on the word of two or three witnesses.
John 8:17-18
It is also written in your Law that the testimony of two men is true.