What does the cross of Christ mean? Is it important to understand what happened there?

What does the cross of Christ mean? Is it important to understand what happened there? Or is it a theoretical puzzle that only scholars and theologians should wrangle about?

Consider Scenario A: Christ died so as to make it possible for "every man" to be saved IF HE DOES SOMETHING FIRST--believes and obeys. And if one does not believe and obey, then the death of Christ on His cross does him no good. The sinner will then have to die for his own sins. He will die the second death just as if Christ had not already died his second death. (Thought through logically, in this view, Christ didn't.)

This view is very reasonable and superficially logical, and is widely popular. The sinner's faith must be exercised prior to his being justified.

Consider Scenario B: When Christ died on His cross, He not only died for every man; He did more--He died the second death of "every man." Thus there is no reason under heaven why any one should ever have to die the second death; Christ already died it for him! The sinner who dies the second death at last is not dying to pay for his sins because his sins were already paid for by the sacrifice of Christ. "The Lord hath laid on Him the iniquity of us all." The sinner dies at last only because of his unbelief, because he despised what Christ actually and already accomplished for him (John 3:16-19). Many do!

Further, in the view of Scenario B, the sacrifice of Christ has enabled the Father to treat "every man" as though he had never sinned, because Christ's death has given "every man" a "[judicial] verdict of acquittal" (Rom 5:15-18, NEB). What Christ has already done for "all men" has preceded any man's personal faith. It's something called "grace."

Does it make any difference to your heart which view you believe?