The idiom to "receive the testimony" means to believe what another person testifies concerning something that he has seen. The abstract noun "testimony" can be translated with a verbal phrase. Alternate translation: "If we believe what men testify" or "If we believe what men say about what they have seen" (See: [[rc://en/ta/man/translate/figs-idiom]] and [[rc://en/ta/man/translate/figs-abstractnouns]])