Parishioners pray at the Emanuel AME Church on Sunday in Charleston, S.C. (David Goldman/Associated Press)

When many relatives of those cruelly murdered in Charleston — by a man who talked and prayed with his victims for an hour before systematically gunning them down — publicly offered their forgiveness, it was stunning and admirable in many ways. Not least of which, it provided a contrast to our political culture. So many are engaged in a search for evidence of their victimization in order to justify their anger. Here, genuine victims of a horrible crime responded with mercy.

The killer chose a historic African American church for a reason. For centuries, black churches have been a place of refuge, a voice for social justice and a target of racist violence. The alleged gunman, Dylann Roof, drove two hours to Charleston, S.C., because he undoubtedly wanted a symbol — and he got one. Against all his intentions, it is now the symbol of a living faith. The killer set out to defile a sacred place and ended up showing why it is sacred.

At the heart of the Christian faith is an impossible demand: to “love your enemies, do good to those who hate you, bless those who curse you, pray for those who mistreat you.” This teaching was demonstrated by its author. The Christian novelist George MacDonald wrote: “ ‘Father, forgive them, for they know not what they do,’ said the Divine, making excuse for his murderers, not after it was all over, but at the very moment when he was dying by their hands.” When we see this type of extreme grace reenacted — as in Charleston — it has a tremendous power and appeal.

The killer was welcomed by the ones he murdered, and then forgiven by the people he deeply harmed. These victims and their families have shown what it means to be followers of Christ. And many of us now feel awed and honored to share the same faith as these remarkable Christians.

The victims were the faithful among the faithful. They were the kind who do much of the praying and working in a church, and who lift the sights and standards of people around them. You can see their legacy in those who survived them, striving so hard to be worthy of their example. A pastor friend in Baltimore, Frank Reid, wrote me: “In the midst of all this talk about security, didn’t the Pastor of Emanuel and those eight people exemplify the real strength and security of the Gospel? In the words of one of Dr. King’s first books of sermons, they exemplified the ‘strength to love.’ ”

That is the right phrase to summarize what we have seen in Charleston: the strength to love. Forgiveness is not something soft or passive. It demonstrates spiritual maturity, strength of character, depth, discipline and steadiness. It is the sign of a determined faith, fighting against every natural human inclination. “I acknowledge that I am very angry,” said Bethane Middleton-Brown, the sister of one of the victims. But “she taught me that we are the family that love built. We have no room for hating.”

A daughter of one victim told an interviewer that everyone, including the killer, deserves a “second chance.” She made her point confidently and without bitterness. Forgiveness is also a form of freedom — a refusal to be ruled by anger or resentment. It is like laying a burden down.

Public lessons will need to be drawn from the Charleston murders — though I cringe when the first response to tragedy is any pet policy project. It should, maybe, be the third response, made a few respectful days later.

The United States clearly has two problems. The first is a problem with racism. These Americans were killed because they were African Americans. How does a long history of hate jump to the next generation? Reflecting on that question should lead us to root out racism in our laws and lives, in the myths we perpetuate and the flags we fly. Second, the United States has a problem with angry young men, radicalized by the Internet. When these two problems are combined, the result is domestic terrorism. There is often no web of conspiracy to track, just signs of murderous intent, which our society must somehow be more alert to confront.

When the Rev. Martin Luther King Jr. preached over the coffins of the children killed in the Birmingham church bombing, he said, “History has proven over and over again that unmerited suffering is redemptive.” That is already true in the examples of the lost; now it needs to be reflected in the conduct of the living.

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