You can translate this in an active form. Alternate translation: "God has made known a way to be right with him without obeying the law" (See: [[rc://en/ta/man/jit/figs-activepassive]])
The words "the Law and the Prophets" refer to the parts of scripture that Moses and the prophets wrote. Paul describes them here as if they were people testifying in court. Alternate translation: "What Moses and the prophets wrote confirms this" (See: [[rc://en/ta/man/jit/figs-personification]])