He studied in the college of the Jesuits at St. Omer, entered the novitiate at Watten, 7 September 1675, and was ordained priest 18 December 1683.
It is stated that Fairfax was appointed professor of philosophy in Magdalen College, and that he was well versed in the oriental languages.
Fairfax was admitted Fellow on 9 January 1688, and two days later was made dean of arts of the college.
After Parker's death Bonaventure Giffard, one of the four vicars apostolic, was on 31 March 1688, by a mandatory letter from the king, nominated president.
Fairfax was attacked in the streets of Oxford and narrowly escaped; and he was formally removed from his fellowship by the Visitor on 30 October 1688.