Paul makes it very clear in the third chapter of Romans. He presents Christ as the propitiation, the mercy seat for our sins. And then he says “for the sins that are past.” And that doesn't mean our sins that are past, it means the sins before the Cross. When God saved Abraham, God saved Abraham on credit. That offering Abraham brought didn’t save him. It pointed to Christ. And when Christ died on the cross, He paid for everything that was past. That's what He meant when He said “it's finished”—for those that are past and for those of us that are future. And the trouble of it is with us future is we want to add something to it. He did it all.