Deuteronomy 17:6
At the testimony of two or three witnesses they must be executed. They cannot be put to death on the testimony of only one witness.
Numbers 35:30
"Whoever kills any person, the murderer must be put to death by the testimony of witnesses; but one witness cannot testify against any person to cause him to be put to death.
Deuteronomy 19:15
A single witness may not testify against another person for any trespass or sin that he commits. A matter may be legally established only on the testimony of two or three witnesses.
Matthew 18:16
But if he does not listen, take one or two others with you, so that at the testimony of two or three witnesses every matter may be established.
2 Corinthians 13:1
This is the third time I am coming to visit you. By the testimony of two or three witnesses every matter will be established.
1 Timothy 5:19
Do not accept an accusation against an elder unless it can be confirmed by two or three witnesses.
Hebrews 10:28
Someone who rejected the law of Moses was put to death without mercy on the testimony of two or three witnesses.
John 8:17-18
It is written in your law that the testimony of two men is true.