To me it is a problem that even if we or anyone else is killed or counted as sheep for the slaughter. that our own death would have anything to do with our own salvation. We are already condemned. how can we pay for our own sin?
Christ paid the price in full, As Paul said, he took the things against us and nailed it to the cross. Jesus said it is finished, he did not say it is begun, now it is your turn to add what i did.
When paul says, FOR THEY SAKE, he means, for the sake of others who need Christ, he sufferes tribulation all day long. so they to can get the message, we should all be this sacrificial for others who need Christ, but our sacrifice will pay for absolutely zero sin debt, or get anyone, including ourselves, out of eternal condemnation.
you also forgot to highlight the most important aspect of that passage.
37 Nay, in all these things we are more than conquerors through him that loved us.
38 For I am persuaded, that neither death, nor life, nor angels, nor principalities, nor powers, nor things present, nor things to come,
39 Nor height, nor depth, nor any other creature, shall be able to separate us from the love of God, which is in Christ Jesus our Lord.
If nothing can separate us from the Love of God based on what his son did. Then we could never lose salvation. period. For nothing would also mean anything we did, or failed to do, once we became children of God born into his family.