Comensoli studied at Street Paul"s (now Holy Spirit) College, Bellambi, New South Wales and obtained a Bachelor of Commerce in economics at the University of Wollongong, working for a time in the banking sector before switching to theology.
From 2011 to 2014 he was an auxiliary bishop of the Roman Catholic Archdiocese of Sydney and the titular bishop of Tigisi in Numidia. On 20 November 2014, Pope Francis appointed Comensoli as Bishop of Broken Bay and his enthronement took place on 12 December 2014. Comensoli entered Street Patrick"s Seminary in 1986 and obtained a Bachelor of Theology in 1989 and a Bachelor of Sacred Theology in 1991 from the Catholic Institute of Sydney.
He was ordained a priest of the Diocese of Wollongong in 1992 by William Edward Murray.
Prior to his appointment as a bishop, Comensoli obtained a Licentiate in Sacred Theology from the Alphonsian Academy in Rome in 2000, a Master of Letters in Moral Philosophy from the University of Street Andrews in 2007 and a Doctor of Philosophy in theological ethics from the University of Edinburgh in 2010. Comensoli was appointed an auxiliary bishop of the Archdiocese of Sydney by Pope Benedict XVI on 20 April 2011.
He was consecrated as a bishop by Cardinal George Pell at Street Mary"s Cathedral in Sydney on 8 June 2011, becoming Australia"s youngest bishop. On 27 February 2014, Bishop Peter Comensoli was appointed by Pope Francis as Apostolic Administrator of the Archdiocese of Sydney following Cardinal Pell"s elevation to the post of Prefect of the newly formed Secretariat for the Economy.
On 18 September 2014, Pope Francis appointed Anthony Fisher as the new Archbishop of Sydney, Comensoli remained the Apostolic Administrator until Fisher"s installation on 12 November.
On 20 November 2014, Pope Francis appointed Comensoli as the Bishop of Broken Bay.
