"And now Jesus is showing them that in his resurrected body his scars are still there. Why is this important? Because now that they understand the scars, the sight and memory of them will increase the glory and joy of the rest of their lives. Seeing Jesus Christ with his scars reminds them of what he did for them--that the scars they thought had ruined their lives actually saved their lives. Remembering those scars will help many of them endure their own crucifixions.
On the Day of the Lord--the day that God makes everything right, the day that everything sad comes untrue--on that day the same thing will happen to your own hurts and sadness. You will find that the worst things that have ever happened to you will in the end only enhance your eternal delight. On that day, all of it will be turned inside out and you will know joy beyond the walls of the world. The joy of your glory will be that much greater for every scar you bear.
So live in light of the resurrection and renewal of this world, and of yourself, in a glorious, never-ending, joyful dance of grace."
Tim Keller in King's Cross: The Story of the World in the Life of Jesus: