Charles felt renewed strength to spread the gospel to ordinary people and it was around then that he began to write the poetic hymns for which he would become known. In January 1739, he was appointed as curate to serve at St Mary's Church, Islington, but was forced to resign when the churchwardens objected to his evangelical preaching. Later that same year, finding that they were unwelcome inside parish churches, the Wesley brothers took to preaching to crowds in open fields. They were influenced by George Whitefield, whose open-air preaching was already reaching great numbers of Bristol colliers. From 1740, John and Charles were the joint leaders of the Methodist Revival and evangelised throughout Britain and Ireland. They were opposed by many Anglican clergy, especially when their appointed lay preachers began to preach in parishes without seeking permission. In Newcastle Charles established its first Methodist society in September 1742, and he faced mob violence at Wednesbury and Sheffield in 1743 and at Devizes in 1747.