Peter John Elliott was born on 1st October 1943 in Melbourne, the elder son of Reverend Leslie Llewellyn Elliott and Irene Ann (June) Rooke.After primary education in government schools, he attended Melbourne Grammar School (1956-1961) and subsequently gained a Master of Arts in History at the University of Melbourne and a Master of Arts in Theology at the University of Oxford, where he was received into the Catholic Church. He returned to Melbourne in 1969 and studied for the priesthood at Corpus Christi College, Glen Waverley.He was ordained a priest by Lawrence Cardinal Shehan, Archbishop of Baltimore and Papal Legate, on 19th February 1973 during the Fortieth International Eucharistic Congress. He worked as Assistant Priest in Springvale, Lilydale and Mentone, where he was Secretary to Bishop John A. Kelly (1979-1984). He also served briefly as Assistant Priest in East Hampton in 1987.In 1984 he commenced studies at the John Paul II Institute for Studies on Marriage and the Family at the Lateran University in Rome and was granted the Degree of Doctor of Sacred Theology in 1986 with a Thesis on the Sacramentality of Marriage.In April 1987 he returned to Rome to be an Official of the Pontifical Council for the Family and was appointed a Chaplain of His Holiness in 1992. During ten years of Vatican service he travelled extensively and was involved in international courses and conferences on the family and marriage in all continents, including the United Nations Conference on Population held in Cairo (1994), the United Nations Social Summit held in Copenhagen, and the United Nations Conference on Women held in Beijing (1995).
On 1st December 1997 he returned to Melbourne as Episcopal Vicar for Religious Education.
He is the General Editor of the Archdiocesan Religious Education Texts, “To Know, Worship and Love”, as well as being the author of books and articles in the fields of Theology, Church History, Catechetics, Liturgy, Marriage and the Family, Apologetics and Demography.In December 2001 he was appointed Parish Priest of East Malvern.In 2002 he was appointed a member of the International Commission for Catechetics of the Congregation for the Clergy.In 2004 he was named Director of the Melbourne Session of the John Paul II Institute for Marriage and the Family and in 2005 he was appointed a Prelate of Honour and subsequently an Auditor at the Synod of Bishops on the Eucharist in October of that year.Pope Benedict XVI appointed him as Titular Bishop of Manaccenser and Auxiliary Bishop of Melbourne on 30th April 2007, and he was consecrated on 15 June 2007.In the Australian Catholic Bishops' Conference he is Bishop Deputy of the Australian Catholic Disability Council and a member of the Bishops Commission for Pastoral Life.