Parker, Theodore (1810–1860)

US Unitarian clergyman and reformer. Serving as Unitarian minister in West Roxbury, he was an associate of William Ellery Channing, Ralph Waldo Emerson, and other Transcendentalists, and became a leader of liberal theological thought; his progressive views forced him to resign his first pastorate (1845) and he became a minister at a new church in Boston. He was active, too, in social movements, including school and prison reforms, temperance, and the abolition of slavery.

Parker was born in Lexington, Massachusetts. He overcame a background of poverty to graduate from Harvard Divinity School in 1836. His health began to fail in 1857 and he gradually withdrew from public life.