What do you do when someone kills somebody you love?

On the same day I watched a docu-mentary about forgiveness, I went home and watched a movie about vengeance.

Which path would I take, if tragedy struck?

Would I be like the Amish of Pennsylvania, who walked stoically to the family of the man who killed their children to tell them they had forgiven him? Or would I be like the character Jodie Foster played in "The Brave One" and buy a gun?

The voices in the documentary, "The Power of Forgiveness," tell me the Amish made the ethical choice.

"Retribution is not part of their vocabulary," says Donald Kraybill, a college professor who has studied the Amish for many years.

After an armed milk driver killed five Amish girls and wounded five others at a schoolhouse in 2006, Kraybill wrote a book about the incredible forgiveness exhibited by the rural, religious community. He's one of the voices featured in the documentary.

Families of Sept. 11 victims also are interviewed. As are Azim Khamisa and Ples Felix, two men who formed an extraordinary bond after Felix's 14-year-old grandson shot and killed Khamisa's 20-year-old son in 1995. Khamisa founded the Tariq Khamisa Foundation, dedicated to teaching kids about nonviolence.

"Forgiveness is something you do for yourself," Khamisa says.

"Anger," he adds, "is not good for you."

Researchers agree.

Studies find that people who forgive have lower blood pressure and pulse rates. Dr. Kathleen Lawler-Row of East Carolina University shares one of her conclusions in the documentary: "Holding onto grudges is harmful to health."

The Rev. James Forbes, the distinguished retired minister at New York City's Riverside Church, doesn't think people should start by trying to forgive their enemies. That's too hard.

"First let them think about how much forgiveness God has had to grant them," he says.

Kraybill says one of the first Bible passages Amish children learn is the Lord's Prayer, which includes this verse: "Forgive us our trespasses as we forgive those who trespass against us." Kraybill didn't mention this in the film, but when I heard him speak last year, he said the Amish fervently believe they must forgive or else God won't forgive them.

As with Khamisa and others in the documentary, Alexandra Asseily argues that forgiveness could be more for your own benefit than for anyone else. Asseily, who witnessed firsthand Lebanon's devastating civil war, is the founder of the Garden of Forgiveness in Beirut.

"Forgiveness allows us to actually let go of the pain in the memory," she says. "And if we let go of the pain in the memory, we can have the memory but it doesn't control us. I think it's the fact that when memory controls us, we are then the puppets of the past."

In the movie "The Brave One," Foster plays a radio personality whose fiancee is brutally beaten to death. She, herself, barely survives. The fear and the memories turn her into a vigilante. In case you haven't seen it yet, I'll stop there.

Except to ask this: Which ones really are the brave ones?