Background
He was born in Piltown, County Kilkenny, Ireland.
He was born in Piltown, County Kilkenny, Ireland.
He studied at Maynooth seminary and the Biblical Institute, Rome was ordained to the priesthood on 16 July 1968 for the Diocese of Ossory Following this was two years of parish work at Street Mary's Cathedral, Kilkenny and Ballycallan parishes.
He taught Scripture in Street Kieran"s College, Kilkenny (1973-1980) before returning to study in Rome and concurrently serving as Spiritual Director at the Pontifical Irish College, Rome (1980-1985). When he returned to Ireland he was appointed to the Faculty of Theology in Maynooth College (1985-1997) rising to the position of Professor of Old Testament. He also taught Hebrew.
On 28 May 1997, he was appointed Auxiliary of Dublin and Titular of Aquae Regiae.
He was consecrated on 21 September 1997. The principal consecrator was Cardinal Desmond Connell.
His principal co-consecrators were Archbishop Luciano Storero, the Apostolic Nuncio to Ireland, and Laurence Forristal, the of Ossory. In May 2005 he was appointed to the Diocese of Galway in succession to Doctor James McLoughlin
In November 2009, there were several calls for Drennan to resign from his post for his inclusion as part of the Murphy Report, surrounding a sexual abuse scandal in the Dublin archdiocese.
Drennan has said that he does not feel disturbed by being mentioned in the Dublin diocesan report.
He said: "The report says nothing negative about me in fact, you know. I don’t think I have any questions to answer, in fact, from my own reflections on the time there. The report itself says that it believed that the Archdiocese acted correctly in addressing the issue that relates to Doctor Drennan especially in the absence of a charge being placed on the priest in question by civil authorities.