One day in August 1678, Charles II was walking in St. James's Park, when an old acquaintance, by name Kirkby, approached, and warned him not to separate himself from his companions, for there was a plot against his life; he might easily be shot even on this walk. Being ordered to come to Whitehall in the evening to give fuller information, Kirkby brought with him a London clergyman of Puritan opinions, Israel Tonge by name, who gave the King detailed information about a Jesuit conspiracy, which was all the more credible as it came from a man who had just apostatised from the Order, Titus Oates. Tonge had written against the morality of the Jesuits; Oates affirmed that he had been commissioned to put him out of the way in consequence; but instead of killing him he had made friends with him. He was in possession of very offensive letters or extracts from letters. Tonge first showed him their object and their full bearing. In the information which Tonge communicated to the King, he was so far himself concerned, and anyhow it was well calculated to excite attention and anxiety.

These extracts were taken from the correspondence of English Jesuits, who lived in London, with members of the old Jesuit seminaries on the Continent, such as the Rector of St. Omer, the Procurator in Madrid and the Provincial in London: Oates had opened the letters which had been entrusted to him to deliver, and so had succeeded in gaining much additional information which he wrote down.