In 1968, Ryan was ordained into the Roman Catholic Church as a deacon and then as a priest. Rather than enter parish ministry, he was granted permission to continue his academic studies. In 1975, after completing an additional degree and while still working towards his doctorate, he was appointed Dean of St Edmund's College, Cambridge. As dean, he was a Fellow of the college and the priest of its college chapel; St Edmund's is unique in that it is the only college of the University of Cambridge with a Roman Catholic chapel. After five years, in 1981, he moved to Canada where he became a Fellow in Western Theology at the Pontifical Institute of Mediaeval Studies of the University of Toronto. There, he taught courses on Dante, Medieval thought, and Medieval history.
Church of England
It was during his time in Canada that Ryan began to question 'many aspects of Roman Catholic teaching' including Papal infallibility. In 1986, he left the Roman Catholic Church, having flown to Scotland to inform his family face to face. That year, he was received into the Church of England by Peter Walker, the then Bishop of Ely. In 1987, Ryan moved from Canada to England. From 1987 to 1990, he held a licence to officiate in the Diocese of Ely; this allowed him to serve as an Anglican priest within the diocese. From 1987 to 1988, he held the Naden Research Studentship in Theology at St John's College, Cambridge. From 1988 to 1990, he was a lecturer in Italian at the University of Cambridge. In January 1991, Ryan moved to the University of Sussex where he had been appointed a senior lecturer in Italian. From 1991 to 2002, he also held Permission to Officiate in the Diocese of Oxford. He was appointed Professor of Italian in 1994. During this time, he served as chairman of the Italian group with the School of European Studies. In 2002, he left Sussex and was appointed Professor Emeritus. In 2002, Ryan returned to the University of Cambridge to take up the appointment of Dean of College of King's College, Cambridge. As such, he 'was the first former Roman Catholic priest to be appointed dean of the college since Tudor times'. This also made him 'the first priest since the Reformation to have been Dean of both a Roman Catholic college and an Anglican college in the same university'. From 2002, he once more held a licence to officiate in the Diocese of Ely.
Death
Ryan died on 20 February 2004, aged 60, after a short illness.
Personal life
In 1987, Ryan married Henrietta McBurney during a service at St George's Chapel, Windsor Castle. For most of their marriage, they lived at Windsor Castle, where Henrietta worked as Deputy Curator of the Royal Collection of Prints and Drawings. They had three children together: a daughter and two sons.
Selected works
Michelangelo, The Poetry. Translated and edited by Christopher Ryan. London: J M Dent, 1997..