Born in Hollis, New Hampshire, Noah was at sixteen a fifer with the American Revolutionary forces at Bunker Hill. By the age of twenty he was writing intently in response to theological questions while working as a shoemaker. When he was given a license to preach as a Congregational minister, he served at a Thornton, New Hampshire church to support his large family. His salary of two hundred dollars a year (if paid) was supplemented by farming and making shoes.

When condemned for his Unitarian views, he was invited by William Ellery Channing to become editor of the Christian Disciple. For five years this was his pivotal Unitarian ministry, along with his being the founder of the Massachusetts Peace Society which spawned the American Peace Society opposing war. Harvard College awarded him an honorary doctorate.