On 10 November 1999, Suriel was appointed the first Bishop of Melbourne, Canberra, Tasmania, South Australia, Western Australia and New Zealand, and was enthroned in his diocese on 4 December 1999.[5] After being appointed to Melbourne he completed his Masters in Religious Education at the Australian Catholic University and received his doctorate from Fordham University on 20 March 2014. His doctoral dissertation was "Habib Girgis, Coptic orthodox Educator and A light in the Darkness" which was reworked into a book published in 2017. He became associate professor and dean at St Athanasius College, a constituent college of the University of Divinity where he lectured in religious education, youth ministry, comparative religions, homiletics and pastoral theology.[6]