Barack Obama has put his religion back into the headlines, trumpeting the power and salvation of faith and asking a church audience in South Carolina to help him become “an instrument of God” and join him in creating “a Kingdom right here on Earth." But the Democratic contender's talk on Sunday of breaking down religious and political differences has some critics questioning the Illinois senator's own beliefs — and those of the man identified as his spiritual adviser — and whether his messages of spiritual inclusion and tolerance have remained consistent. Obama has written and spoken about being inspired by...