A religious man is a person who holds God and man in one thought at one time, at all times, who suffers in himself harm done to others, whose greatest passion is compassion, whose greatest strength is love and defiance of despair.

Abraham Joshua Heschel (1907-1972) Polish-American rabbi, theologian, philosopher

“What Ecumenism Is” (1963)
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Collected in Susanna Heschel, ed., Moral Grandeur and Spiritual Audacity (1996). In other essays in the book, he uses the first clause ("a person who holds God and man in one thought, at one time, at all times") as a definition of a "prophet."