During one scene of The Simpsons, Bart is in a minigolf match against Todd Flanders (of the ultra-Christian Flanders family). Homer sees the Flanderses praying before the match and says, "Hey, Flanders! I already did the same thing, and we can't both win!" Since he prayed first, Homer argues, God is on his side.

Questioning just how much God cares about who wins a sporting event is a pretty old joke, but that doesn't make it any less true. I guarantee that after the World Series this month, someone on the winning team will thank God not for his talent but for the victory itself.

While occasionally strange—one didn't hear Green Bay's Reggie White blaming God for the 1998 Super Bowl defeat quite like he thanked him for the 1997 victory—it illustrates the point that sport and Christianity seem to have a natural, ever-present link in American culture. In fact, it may be the area of American popular culture most infused and identified with Christianity.

It hasn't always been that way, as Wheaton College professors Tony Ladd and James A. Mathisen recount. "Evangelical muscular Christianity was possible in the 1880s because of the rapid acceptance of sport in American life," they argue, "especially as it encouraged opportunities for the YMCA on college campuses." But in the early part of this century, evangelical Christians became disillusioned with sport and "disengaged" from it. Chicago White Stockings ball player Billy Sunday, the greatest athlete-turned-evangelist in Christian history, even became antagonistic to his former career.

As Ladd and Mathisen summarize, "When sport moved in increasingly secular directions in the early twentieth century, Protestants moved accordingly—but in two separate directions. While ...