2 Corinthians 13:1-2

1This is the third time that I am visiting you. Every fact shall be sustained and confirmed by the testimony of two or three witnesses.

2I have already warned those who have sinned in the past and all the rest as well, and I warn them now even though I am absent [from you] as I did when I was with you the second time, that if I come back I will not spare anyone,