Mankind were one nation once, and Allah sent them prophets with good tidings and with warnings, and sent down with them the Book in truth, to judge between men in that wherein they disagreed; but only those unto whom the scripture was given disagreed therein after manifest signs had come to them, through selfishness and stubborn pride (or hatred) amongst themselves; and Allah guided by His Will the believers to the truth concerning that wherein they disagreed, for Allah guides whom He will unto the straight path.