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“The toleration of those that differ from others in matters of religion is so agreeable to the Gospel of Jesus Christ, and to the genuine reason of mankind, that it seems monstrous for men to be so blind as not to perceive the necessity and advantage of it in so clear a light.”
Locke argues that religious difference should not by itself justify coercion or persecution, grounding toleration both in his reading of Christianity and in a broader appeal to human reason.
Source note: A Letter Concerning Toleration (1689), public-domain text also preserved in The Works of John Locke. Locke immediately distinguishes civil government from religion and argues that persecution should not be disguised as care for souls. His historical position had limits, so this page does not present the letter as a complete modern theory of equal religious freedom.