To participate in the sacrifice of the Mass, we must be free of mortal sin. So let us say we have put ourselves into the cell of sin, over and over again. What then? We must put ourselves into the confessional box, over and over again. Then we can receive Christ; and then we can, in turn, freely put ourselves into the cup of sacrifice, to be poured out for each other. That is how it works. Jesus told us so. This is what he told us to do.