The care of the salvation of men’s souls cannot belong to the magistrate; because, though the rigour of laws and the force of penalties were capable to convince and change men’s minds, yet would not that help at all to the salvation of their souls. For there being but one truth, one way to heaven, what hope is there that more men would be led into it if they had no rule but the religion of the court and were put under the necessity to quit the light of their own reason, and oppose the dictates of their own consciences, and blindly to resign themselves up to the will of their governors and to the religion which either ignorance, ambition, or superstition had chanced to establish in the countries where they were born? In the variety and contradiction of opinions in religion, wherein the princes of the world are as much divided as in their secular interests, the narrow way would be much straitened; one country alone would be in the right, and all the rest of the world put under an obligation of following their princes in the ways that lead to destruction; and that which heightens the absurdity, and very ill suits the notion of a Deity, men would owe their eternal happiness or misery to the places of their nativity.
Source: John Locke. A Letter Concerning Toleration, paragraph 2, October 3, 1689. Daily Dabble in the Classics is compiled, and edited (with occasional commentary) by The Moral Liberal, Editor In Chief, Steve Farrell.