Caleb Cushing

The Normans came over, lance in hand, burning and trampling down every thing before them, and cutting off the Saxon dynasty and the Saxon nobles at the edge of the sword; but the right of petition remained untouched.

There are clearly many good politicians who are guided by religious belief, so the mix can work. But there's a line to be drawn. It would be hugely dangerous for a country's laws to be set by the scriptures, and particularly those of the expansionist religions.