He was the first full-time minister of Abyssinian Congregational Church in Portland, Maine, where he led a station on the Underground Railroad.
Freeman returned to his native New Jersey to attend Rahway Academy, and later transferred to the Oneida Institute in Whitesboro, New York.
Freeman was one of four African Americans in the first year class of 33; others were Amos Beman, who became a good friend; Alexander Crummell, and Henry Highland Garnet.
[1] Upon graduating from Oneida Institute in the early 1830s, Freeman moved back to New Jersey, first to New Brunswick, then Newark, to teach in the "colored" public schools.
In 1839 in Newark, Freeman married Christiana Taylor Williams (1812-1903), born in Red Hook on Hudson, New York.
Freeman became the most well-known African American in Maine because of his leadership there; he was a strong supporter of education and also ran a school affiliated with the church.
His was one of 5 names attached to the address of the convention to the people of the United States published under the title, The Claims of Our Common Cause, along with Frederick Douglass, James Monroe Whitfield, Henry O. Wagoner, and George Boyer Vashon.
Freeman lived in Brooklyn in the mid-1850s, he secretly sheltered and aided Anna Maria Weems, a young fugitive slave, on her journey to freedom in Canada.
They met Dr. Ellwood Harvey of Philadelphia in front of the White House in November 1855, and Weems pretended to be a male buggy driver.
Freeman accompanied Weems from there by train to Canada, where she reached safety at her uncle and aunt's house in Ontario.