And I heard a loud voice from the throne saying, "Behold, the dwelling of God is with men. He will dwell with them, and they shall be His people, and God Himself will be with them; He will wipe away every tear from their eyes, and death shall be no more, neither shall there be mourning nor crying nor pain any more, for the former things have passed away."
The mercy we receive in the sacrament of Reconciliation is not something other than the Ultimate Mercy we shall receive from God at the end of time. It's the same thing, experienced day by day until we grow into people who are capable of receiving and dwelling in it eternally. On the Last Day, God will not have changed a jot — we will have changed. We will finally be mature enough in Christ to be what the Blessed Virgin always was — younger than sin.