Tesimond spent most of his adult life in Italy, under the name of Philip Beaumont, (Beamond, Bémont). Later, Tesimond studied, among other things, theology in Messina, where he afterwards taught philosophy. He was ordained, some time before he left on the English Mission, in November 1587. He arrived at Gravesend on 9 March 1598. Tesimond worked for eight years as a missioner with Edward Oldcorne in Worcestershire and Warwickshire under the name "Father Greenway", primarily out of Hindlip Hall. He was professed as a Jesuit on 28 October 1603.