While in his early 20s, Campbell wrote several moral essays under the pseudonym "Clarinda". and published them in a local paper. In 1820, his debate with the
Presbyterian John Walker was published, reminding him of the efficacy of writing and publishing. Campbell edited and published two journals. The first was the
Christian Baptist, which he edited from 1823 through 1830. The second was
The Millennial Harbinger, which he began in 1830 and continued to edit until his death in 1866. He became less active in it during the 1850s. In both, he advocated the reform of Christianity along the lines as it was practiced on the American frontier. He encouraged contributions by writers who thought differently from him, and the journals encouraged a lively dialogue about issues in the reform movement. Campbell expanded his printing operation in 1830 for the
Millennial Harbinger. Campbell compiled and published a translation of the New Testament under the title
The Living Oracles. Published in 1826, it was based on an 1818 translation by George Campbell, James MacKnight and Philip Doddridge, and included edits and extensive notes by Campbell. His known works include: •
The Living Oracles (1826) – Campbell's translation of the New Testament •
Psalms, Hymns and Spiritual Songs (1828) •
Prospectus of the Millennial Harbinger (1829) •
Delusions: An Analysis of the Book of Mormon (1832) • ''The Christian Preacher's Companion'' (1836) •
The Christian System (1839) – summary of Campbell's theology •
The Christian Hymnbook (1843) •
A Tract for the People of Kentucky (1849) •
Christian Baptism—Its Antecedents and Consequents (1851) •
The Acts of the Apostles (1858) – Campbell's translation •
Memoirs of Elder Thomas Campbell (1861) •
Popular Lectures and Addresses (1863) •
Familiar Lectures on the Pentateuch (1867) ==Public debates==