24 For Jesus is not entered into the holies made with hands, the patterns of the true: but into heaven itself, that he may appear now in the presence of God for us.
Christ freed us from the need for blood sacrifice.
How can we perform a blood sacrifice after we are dead?
Christ is the last blood sacrifice that man needs.
But the sins against man also need atonement. Purgatory is how we atone for the sins against me that we didn’t atone for while alive.