All it takes to be a Muslim is to say, and mean, “There is no God but God, and Mohammad was his prophet.” This doesn’t mean Jesus wasn’t a prophet, too. It is simply a statement accepting that Mohammad was as well. That’s right, Christians – you’re one head nod away from a pilgrimage to Mecca!

The similarities and differences between the closely related Islamic and Christian faiths are intriguing and revealing. The thick, bold line many practitioners of both faiths draw is in fact much more blurry than they think. Small differences abound, but an overall sense of cohesion is …