member of a Christian group founded about 1848 by John Thomas, who, after studying medicine in London, emigrated to Brooklyn, New York. He at first joined the followers of Thomas and Alexander Campbell, founders of the Disciples of Christ (Christians), but eventually he began preaching independently, largely applying Hebrew prophecy and the book of Revelation to current and future events. Both in the United States and in Great Britain he gathered a number of adherents. The name Christadelphian was adopted during the American Civil War (1861-65), when the followers of Thomas organized formally to justify their objection to military service.
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