Matthew 18:16

But if he will not listen, take one or two others with you, so that everything may be supported by the testimony of two or three witnesses.

2 Corinthians 13:1

This will be my third visit to you. Any charge must be sustained by the evidence of two or three witnesses.

1 Timothy 5:19

Do not listen to an accusation made against an elder, unless it is supported by two or three witnesses.

Hebrews 10:28

Anyone who breaks the Law of Moses is put to death without any show of pity, on the evidence of only two or three witnesses.

John 8:17-18

Why, in your own Law it is stated that the testimony of two persons is valid.

Treasury of Scripture Knowledge

Summary

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.

Bible References

General references

Matthew 18:16
But if he will not listen, take one or two others with you, so that everything may be supported by the testimony of two or three witnesses.
John 8:17
Why, in your own Law it is stated that the testimony of two persons is valid.
2 Corinthians 13:1
This will be my third visit to you. Any charge must be sustained by the evidence of two or three witnesses.
1 Timothy 5:19
Do not listen to an accusation made against an elder, unless it is supported by two or three witnesses.
Hebrews 10:28
Anyone who breaks the Law of Moses is put to death without any show of pity, on the evidence of only two or three witnesses.