Thomasites / The Antipas > Christadelphian.
THE term Christadelphian, like the faith of those who adopt it, was constructed by John Thomas, M.D. Consequently, before the latter part of his life none was ever called by that name. It was appropriate that he abandoned the old name Christian, which had been honoured by the apostles and borne by saints and martyrs along the centuries. By inventing another name, which neither prophet nor apostle ever heard, he left the God-honoured designation for those entitled to it. It was late in his life that he originated this new name. Before that his followers were generally known as Thomasites; and properly so, because, though not accepted by them, thus was expressed their relation to him, as no one ever embraced his doctrines who did not, either directly or indirectly, obtain them from him. Accordingly, his tombstone is inscribed - "He demonstrated the unscriptural character of popular Christianity, and made manifest the long lost faith of the apostles, and at his death left behind him, as a result of his labours, a body of people in different parts of the world, known as Christadelphians." He died in March, 1871.
some Thomasites, both in this country and in America, refused to adopt the new-fangled term. It was repudiated by the organ of one of the Thomasite sections, published here, thus -
"They have assumed the name 'Christadelphians,' said to mean 'Christ's Brethren.' They hold that this name is scriptural and apostolic ... Neither the name nor the Greek expression from which it is derived occurs in Scripture. Can it then be scriptural? The apostles never used it; can it then be apostolic? Indeed the assertion is sufficiently refuted by the acknowledged fact that 'the name was first adopted in Illinois, during the civil war.' The roots of the Greek words christou adelphoi, according to the analogy of telegraph, epitaph, photograph, etc., give christadelphs. The word 'Christadelphians' contains another element; the affix an, which materially modifies the meaning. This affix sometimes denotes a doer, as in tragedi-an. More frequently, especially with names of places, it denotes of, or pertaining to, as Europe-an, belonging to Europe. With the names of persons it denotes a follower, as Wesley-an, a follower of Wesley; Christi-an, a follower of Christ. Hence 'Christadelphians' properly signifies not the brethren of Christ themselves, but followers of the brethren of Christ."
Thus, then, the pedantry of Dr. Thomas (his writings mostly bear foreign names, as Elpis Israel, Eureka, Phanerosis, Anatolia) led him to a faulty construction, so that instead of naming his followers "Brethren of Christ" he really named them "Followers of Brethren of Christ," which is a widely different thing, for some of Christ's brethren wander very far from the truth. But be that as it may it is certain that the Brethren of Christ, the Church of God, have not been left nameless these eighteen hundred years; nor is it less certain that Dr. Thomas was neither commissioned nor competent to invent a name for them.
+ > "Glance at the History and Mystery of Thomasism," published A.D. 1869