Richard Clarke has been elected head of the Church of Ireland, succeeding archbishop Alan Harper who retired at the end of last month.
The 63-year-old bishop of Meath and Kildare has been appointed the new Archbishop of Armagh and primate of All Ireland.
Dr Clarke, a widowed father of two from Dublin, is the 105th in the succession of abbots, bishops and archbishops of Armagh since St Patrick.
He said: "I look forward to fresh challenges and joys, along with new friendships and discoveries, in the phase of ministry in the Gospel that now lies ahead, both in the Diocese of Armagh and within the wider fellowship of the Church of Ireland and beyond."
His election will take effect from December 15th this year when he will be enthroned at St Patrick's Cathedral in Armagh.
Dr Clarke said: "I truly feel neither worthy of the heritage into which I am to enter, nor adequate for the tasks that lie ahead. The God of Christian belief is, however, a God of grace rather than a God who looks for human self-sufficiency.
"All I can pledge is that I will give this task the very best of which I am capable and the prayer of all of us must be that God in his grace will enable some good to come from this."
Dr Clarke said one of the main challenges confronting him and the church's 480,000 members would be secularism.
"That to me is the danger, to think that religious faith is an add on and the normal default is to be without faith," he said.
Dr Clarke was educated at Trinity College Dublin and King's College London.
He began as a minister in Holywood, Co Down and worked in Dublin, as dean in residence at Trinity; St Fin Barre's Cathedral in Cork and Perth in Scotland.
PA