Deuteronomy 19:15

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 can not so easily carry on a cheat, (Calmet) as was seen in the case of Susanna. [Daniel xiii.] (Haydock) --- The law is satisfied with moral certainty. (Calmet)