Randall Balmer was a late convert to sports talk radio, but he quickly became addicted, just like millions of other devoted American sports fans. As a historian of religion, the more he listened, Balmer couldn't help but wonder how the fervor he heard related to religious practice. Houses of worship once railed against Sabbath-busting sports events, but today most willingly accommodate Super Bowl Sunday. On the other hand, basketball's inventor, James...