Under Thaddeus Harris’s tenure at the First Church it was seen that the congregation had outgrown its accommodations, so the Second Church was set off to be located at Codman Square.
No. 456 Rev. John Codman
The following is from Second Church’s website https://secondchurchdorchester.org/about-us-2/history/
“On November 19, 1804, eighty residents of the town formed themselves into a “Dorchester Meeting House Company” for the purpose of erecting “this great church of ours” within 100 rods of Baker’s Corner (now Codman Square).
Dr. John Codman, member of an influential family, graduate of Harvard, and also attended Edinburgh University, Scotland, was ordained on December 7, 1808, as first minister of Second Church in Dorchester. Dr. Codman’s ministry has been the longest in the history of Second Church. A note of interest — during Dr. Codman’s ministry Daniel Webster regularly attended Second Church when he was in Dorchester. Also, John Adams, second president of the United States, attended services there.
Unitarianism existed as a faith but not as a denomination. Dr. Harris and the First Parish belonged to the liberal order, and the new or Second Church included those who were in sympathy with traditional Congregational views. The new minister of the Second Church possessed strong Orthodox views. Liberal members of the Second Church disagreed with Dr. Codman, because he refused to exchange pulpits with the liberal members of the Boston Ministers’ Association. A long and bitter controversy followed and led to a confrontation.
Those who were dissatisfied agreed to sell Dr. Codman their pews and to withdraw from the Church membership. The seceders organized the Third Religious Society (called then the New South Parish), a distinct Unitarian parish. Their first meeting was May 6, 1813, when the construction of a meeting house was planned.
Dr. Codman died on December 23, 1847, but a few days before his death, riding with his friend, Rev. William Allen, D.D., in a pleasant field a short distance in front of this meetinghouse, Dr. Codman said, “I intend to offer this field to my parish for a cemetery and here I wish to lie in the midst of my people.” Thus it was that Second Church came into possession of the Codman Cemetery.
The following is a footnote in the Clapp genealogy.
Rev. John Codman, D.D., was born in Boston, Aug. 3, 1782. He was son of Hon. John Codman and Margaret Russell his wife, grandson of John, of Charlestown and great-grandson of Capt. John, who came to an untimely end by being poisoned by his three negro slaves about the middle of the 18th century. It is recorded by the biographer of Rev. Dr. C. that one of these slaves was executed for his crime on the northerly side of the Cambridge road, about a quarter of a mile above the peninsula, and that another, a female, was burned at the stake, about ten yards from the gallows!—the only instance, it is said, in the history of this country, of that method of punishment under the authority of the law. Dr. Codman graduated at Harvard College in 1802, studied for the ministry under the Rev. Henry Ware, then of Hingham, and in 1805 embarked for Europe, to finish his theological studies there. After spending three years broad, he returned home, and in August, 1808, first preached to the Second Church in Dorchester, then recently organized, their new meeting-house having been dedicated Oct. 30, 1806. He was ordained pastor of this church Dec. 7, 1808, the Rev. Dr. Channing (from whom he very soon after separated in theological belief) preaching the ordination sermon. In about a year after his settlement, commenced the celebrated controversy between him and many members of the parish, which lasted for three years, but neither the merits nor the details of which can be here entered into. In 1821, an interesting journey by Dr. C. and his wife was made to the state of Georgia, including a Sunday passed at Midway, among the descendants of the people of Dorchester who emigrated thence in 1695. They then took passage for Europe, returning home the next year. Two other visits to Europe were afterwards made by Dr. C. The position attained by Dr. Codman as pastor of the Second Church, and as a leading and able minister in the denomination to which he belonged, was elevated, and his death, which took place Dec. 23, 1847, in his 66th year, was much lamented. (Text from the entry for Joseph Clapp in The Clapp Memorial. Record of the Clapp Family in America … Ebenezer Clapp, compiler. (Boston: David Clapp & Son, 1876))
“The remains of Dr. Codman were transferred to the family tomb in the Cemetery the day the cemetery was consecrated. The members of the parish have erected a granite monument to his memory and inscribed upon it ‘Our Pastor.’ The first interment was of the body of Mrs. Mary C. Sanborn, and took place on October 19, 1848.” History of the Town of Dorchester, Massachusetts. (Boston, 1859).
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John Codman by Copley at Harvard Art Museums