Deuteronomy 17:6
At the mouth of two witnesses, or three witnesses, shall he who is to die 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 slain at the mouth of witnesses: but one witness shall not testify against any person that he 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 a matter be established.
Matthew 18:16
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.
2 Corinthians 13:1
This is the third time I am coming to you. "At the mouth of two or three witnesses shall every word be established."
1 Timothy 5:19
Don't receive an accusation against an elder, except at the word of two or three witnesses.
Hebrews 10:28
A man who disregards Moses' law dies without compassion on the word of two or three witnesses.
John 8:17-18
It's also written in your law that the testimony of two people is valid.