Some years ago I read about Charles Brown, a World War 2 pilot on his first mission, just before Christmas, 1943. His B-17 had been shot to pieces by German fighters and anti-aircraft guns. Half his crew was wounded, his tail gunner was dead, and he was flying alone over Germany, barely able to keep the plane aloft.

Then, as if things could not be more desperate, Brown looked to his left and locked eyes with Franz Stigler, an ace German fighter pilot flying no more than a few feet off the B-17’s wing. Brown’s blood went cold; this was the end.

Stigler, the German pilot, was thirsty for revenge. The Allied forces were responsible for his brother’s death, and they had been relentlessly bombing his country’s cities. Now he had a chance to retaliate. But as he came up behind the low-flying bomber, he recognized that it was shot to pieces. He could see the dead and wounded crew inside.

Stigler, with one hand on the trigger and another on his rosary, couldn’t shoot. Instead, he nodded at Brown and protectively escorted the bomber over the North Sea and to the edge of Allied airspace. He took one last look at the American pilot, saluted, and peeled away.

Brown landed safely, survived the war and eventually returned home where he would marry, have children, go to work for the State Department, and retire in Florida. But the older he got, the more Brown thought about that December day above Germany. He decided that he must find that German pilot.

His search was showing little progress when he received an unexpected letter. It was from Franz Stigler! It read, “Dear Charles, all these years I wondered what happened to that B-17, did she make it or not?” Stigler was now retired in Canada and was making the same improbable search. The two pilots became best of friends, meeting as often as possible, corresponding, and talking weekly by phone.

Brown was forever grateful for Stigler’s gift of mercy – his whole life had been possible because of it. But the event changed Stigler’s life as well. He said, “In the war I lost my brother, my friends (of the 28,000 pilots who flew for the German air force, only 1,200 survived), and I lost my country. The war cost me everything. Charles Brown was the only good thing that came out of that war for me. It was the one thing I could be proud of.”

Stigler and Brown died within months of each other in 2008. A book found in Charles Brown’s library after their deaths, a gift from Stigler, had this written on the flap: “On the 20th of December, 1943, four days before Christmas, I had the chance to save a B-17 from her destruction, a plane so badly damaged it was a wonder that she was still flying. The pilot, Charles Brown, is for me, as precious as my brother once was. Thank you Charlie. Your Brother, Franz.”

Few stories illustrate so well how transformational mercy can be. It reconciles enemies, heals old wounds, extinguishes vengeful fires, and gives life. And it accomplishes these things, not only for the recipient of mercy, but also for the one who offers mercy.

Mercy is a shared gift, a gift for both the offender and the offended; for the one who must be pardoned, and the one who pardons; for the violator and the violated. When we replace vengeance with compassion; retaliation with grace; and punishment with forgiveness, then, like no other moment, we are giving life to the world.

So who in your life could best be served by the gift of mercy this Advent Season? That old enemy? A shystering, former business partner? A parent, child, neighbor, or sibling? There’s usually no shortage of offenders, just a shortage of forgiveness. Maybe it’s finally time to ask God for the grace to grace others, to cling to your rosary, and take your finger off the trigger. The person you save might be yourself.