The church must be reminded that it is not the master or the servant of the state, but rather the conscience of the state. It must be the guide and the critic of the state, and never its tool. If the church does not recapture its prophetic zeal, it will become an irrelevant social club without moral or spiritual authority. If the church does not participate actively in the struggle for peace and for economic and racial justice, it will forfeit the loyalty of millions and cause men everywhere to say that it has atrophied its will.

Martin Luther King, Jr. (1929-1968) American clergyman, civil rights leader, social activist, preacher

Strength to Love, ch. 6 “A Knock at Midnight,” sec. 3 (1963)
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