 Ordained in the Congregational church in 1785, Haynes pastored a church in Torrington, Connecticut for three years.In 1788, Haynes accepted a call to pastor the West Parish Church of Rutland, Vermont (now West Rutland's United Church of Christ), where he remained for the next 30 years.He then moved to a temporary pastorate at Manchester, Vermont, and finally to South Granville, New York, where he was pastor of South Granville Congregational Church.