 He served as an assistant priest in Blackheath, London, from 1972 to 1977.He was consecrated as coadjutor bishop to the Metropolitan of Glastonbury in 1977 and succeeded him as Metropolitan of Glastonbury in 1979.In 1994, Mar Seraphim led much of the UK branch of the church into union with the Coptic Orthodox Church of Alexandria, thus forming the British Orthodox Church.