“If I stay there and bow my head, I am sanctioning what they are doing. I don’t sanction it because I think it’s wrong,” said Hughes, who grew up in the Christian Science church. “I give no validity to mysticism at all.”

Warren Hughes is 79, and until a year ago, he had never met anyone like himself: a black atheist. In the atheists groups he has joined, he was often the only black person.

It’s been lonely, he said, but that is beginning to change. The number of blacks who identify as nonreligious increased from 6 percent in 1990 to 11 percent in 2008, according to a survey by the Pew Forum on Religion & Public Life.

At the same time, blacks remain far more religious than most Americans. They have the highest percentage of church membership of any racial group—87 percent—and the highest percentage of people who say they absolutely believe in God, Pew says.