Every morning, sometimes as early as 5:30 a.m., a short religious passage comes across President Obama's BlackBerry, sent by one of his aides. At other moments, Obama prays privately, his advisers said. And when he takes his family to Camp David on the weekends, a Navy chaplain ministers to them, with the daughters attending a form of Sunday school there. More than a year into his presidency, Obama has not chosen a church in Washington, and has attended services just four times. No single figure has assumed the role of spiritual adviser -- publicly, at least -- or filled the...