1 John 5:8
And there are three that bear witness on earth, the Spirit and the water and the blood; and these three agree in one.
But if he will not hear thee, then take with thee one or two more that in the mouth of two or three witnesses every word may be established.
One witness shall not be valid against a man for any iniquity or for any sin, in any sin which he should commit. At the mouth of two witnesses or at the mouth of three witnesses, shall the matter be established.
2 Corinthians 13:1
This third time I am coming unto you. In the mouth of two or three witnesses shall every word be established.
1 Timothy 5:19
Against an elder do not receive an accusation, unless there are two or three witnesses.
He that despised the law of Moses died without mercy under two or three witnesses:
At the mouth of two witnesses or three witnesses shall he that is worthy of death be put to death, but at the mouth of one witness he shall not be put to death.