Luke records what the other Gospels do not: one of the two men crucified with Jesus turned toward Him. He did not deny what he had done. He said they were receiving the due reward of their deeds, and that this man had done nothing wrong. Then he asked for one thing, to be remembered when Jesus came into His kingdom.
Jesus answered with the word "today." No time remained for restitution or a changed life. What remained was the truth, a plea, and the mercy of God. The Church has never used this scene to excuse delay. It has used it to say that no hour, not even the last one, is beyond the reach of Christ. Tradition calls him Dismas and keeps his feast on the twenty-fifth of March.
Truly, I say to you, today you will be with me in Paradise.
Luke 23:43, RSV-CE