involved. He later claimed to have won hundreds of converts to the Church of Ireland. However, the conversions ended when William Magee, the Anglican Archbishop of Dublin, ruled that converts were obliged to swear allegiance to George IV as the rightful king of Ireland. Darby resigned his curacy in protest. Soon afterwards, in October 1827, he fell from a horse and was seriously injured. He later stated that it was during this time that he began to believe that the "kingdom" described in the Book of Isaiah and elsewhere in the Old Testament was entirely different from the Christian church. Over the next five years, he developed the principles of his mature theology – most notably his conviction that the very notion of a clergyman was a sin against the Holy Spirit, because it limited the recognition that the Holy Spirit could speak through any member of the Church. During this time (1827–28) he joined an interdenominational meeting of believers (including Anthony Norris Groves, Edward Cronin, J. G. Bellett, and Francis Hutchinson) who met to "break bread" together in Dublin as a symbol of their unity in Christ. By 1832, this group had grown and began to identify themselves as a distinct Christian assembly. As they travelled and began new assemblies in Ireland and England, they formed the movement now known as the Plymouth Brethren. It is believed that John Nelson Darby left the Church of Ireland around 1831. He participated in the 1831–33 Powerscourt Conference, an annual meeting of Bible students organized by his friend, the wealthy widow Lady Powerscourt. At the conference, Darby publicly described his ecclesiological and eschatological views, including the pre-tribulation rapture. For about 40 years William Kelly (1821–1906) was his chief interpreter and continued to be a staunch supporter until his own death. Kelly in his work John Nelson Darby as I knew him stated that "a saint more true to Christ's name and word I never knew or heard of". Darby defended Calvinist doctrines when they came under attack from within the Church in which he once served. His biographer Goddard states, "Darby indicates his approval of the doctrine of the Anglican Church as expressed in Article XVII of the Thirty-Nine Articles" on the subject of election and predestination. Darby said: Later years Darby travelled widely in Europe and Britain in the 1830s and 1840s, and established many Brethren assemblies. He gave 11 significant