I don’t quite see the relevance of the 1 Peter text, but with respect to James 2:10 I think we simply have to accept that Jesus was righteous and blameless according to the Law, as both the rich young ruler and Paul were (Lk. 18:20-21; Phil. 3:6). He didn’t murder. He didn’t commit adultery. He fulfilled the role that Israel had failed to fulfil. But most importantly, he was obedient. You can speculate that a sacrifice for the sins of the world requires that Jesus was God, but the New Testament itself nowhere makes that argument.
how to tell the biblical story in a way that makes a difference