Substitution? Example?

Something else I've wondered is how is it that Yeshua's death is a substitute death? Scripture says no man can pay the price for another (2 Chronicles 25), so... isn't it his LIFE that is accounted? We do still have to die after all, die daily to ourselves. Wasn't his death the physical demonstration of what we have to do?
Yet, scripture also says he died FOR us. He accepted the guilt of every sin ever committed when the Father laid it on him and he took the punishment of death. Here is where the analogies come in and start getting confused; when we become part of the body of Christ, death is in our past, we have died because of sin since he did. The confusion is calling ourselves the "bride of Christ", are we part of him or a bride? It's not literal so no big deal really. A wife and husband are "one" too, like Yeshua is with the Father and like we are to be with them both, so I guess it still would work. Not confusing after all.