Perhaps the most notable of the religious leaders on the anti-slavery side was Reverend William Ellery Channing. His book, Slavery, caused a stir and shed much light on the religious arguments against slavery. His concept of natural religion emphasized the rights of man, which he felt took precedence over the Biblical, or "revealed" religion. A century later, his work again had relevance as it offered support for the Civil Rights Movement.
Natural Religion Against Slavery: William Ellery Channing on Slavery provides a fascinating look at one aspect of the most divisive issue in American history.