The arguments in Locke's Letter on Toleration are that there should be a separation between church and state and that there should be religious toleration. Locke's arguments for religious toleration connect nicely to his account of civil government. Life, liberty, health and property are our civil interests that should be the proper concen of a civil government. The civil government can use force and violence where it is necessary to preserve civil interests against attack. This should be the central function of the state. One's religious views on salvation, however, are not within the realm of civil interests, so they are outside of the legitimate concerns of the the civil government. Locke is not only concerned with the notions of life, liberty, health and property, but also with the right of freedom to choose one's own religious beilef. Locke holds that the use of force by the state to get people to hold a certain belief or engage in certain ceremonies or practices is illegitimate.
The chief means which the civil government has at her disposal is force, but that force is not an effective means for changing or maintaining belief. Suppose then, that the civil governent uses force to make people profess that they believe. Locke states:
"A sweet religion, indeed, that obliges men to dissemble, and tell lies to both God and man, for the salvation of their souls! If the magistrate thinks to save men thus, he seems to understand little of the way of salvation; and if he does it not in order to save them, why is he so solicitous of the articles of faith as to enact them by a law". (p. 30)
This argument is certainly convincing because there needs to be a seperation between the church and the state. If there was...