Campion finally entered England in the guise of a jewel merchant. He arrived in London on June 24, 1580, and at once began to preach. His presence became known to the authorities, and the diffusion of the challenge he threw down in the form of a declaration, known as the "Challenge to the Privy Council" to his allies and as "Campion's Brag" to his enemies, made his position more difficult. He led a hunted life, preaching and ministering to Catholics in Berkshire, Oxfordshire, Northamptonshire, and Lancashire.
During this time he was writing his Decem Rationes ("Ten Reasons"), a rhetorical display of reasons against the Anglican Church. The book was printed in a clandestine press at Stonor Park, Henley, and 400 copies were found on the benches of St Mary's, Oxford, at the Commencement, on June 27, 1581. It caused great sensation, and the hunt for Campion was stepped up. On his way to Norfolk, he stopped at Lyford in Berkshire, where he preached on July 14 and the following day, by popular request. Here, he was captured by a spy and taken to London with his arms pinioned and bearing on his hat a paper with the inscription, "Campion, the Seditious Jesuit".
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