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 the matter be established.
Read Chapter 19
Augustine of Hippo
AD 430
As a matter of fact, a single witness generally speaks the truth, while a mob may tell lies. And the world, in its conversion to Christianity, believed one apostle preaching the gospel rather than the mistaken multitude who persecuted him. Against Faustus, a Manichaean
Therefore if a people composed of a great multitude was found a false witness, how must it be understood, “In the mouth of two or three witnesses every word shall stand,” except that in this way. The Trinity, in which is unending stability of truth, was revealed through a mystery. Do you want to have a good case? Have two or three witnesses, the Father and the Son and the Holy Spirit. .
[Christ] did then truly rise, and after he had risen, he was seen again by his disciples. And the twelve disciples were witnesses of his resurrection, testifying not with words meant to please but contending for the truth of the resurrection even unto torture and death. Further, “on the word of two or three witnesses every word may be confirmed,” according to Scripture. There are twelve witnesses to the resurrection of Christ, and do you still disbelieve in the resurrection? Catechetical Lecture
One would suffice to make an enquiry into the affair, and to oblige the person accused, in pecuniary matters, to take an oath that he owed nothing. (Maimonides)
Stand. This expression was become proverbial, to denote the certainty of a thing, Matthew xviii. 16., and 2 Corinthians xiii. 1. Two witnesses cannot so easily carry on a cheat, (Calmet) as was seen in the case of Susanna. (Haydock)
The law is satisfied with moral certainty. (Calmet)
At the birth of the Savior, then, there was fulfilled that divine sentence which says, “Every word shall stand with two or three witnesses.” For see, the Word of God is born with the Trinity as witness. For indeed, in the womb of holy Mary—when the Holy Spirit comes upon her, when the Most High overshadows her, when Christ is begotten—there is implied a confession of faith in him. ..