The Pope has accepted the retirement request from the Archbishop of Dublin Diarmuid Martin, under whose auspices 10 Kildare parishes fall.
He turned 75 earlier this year and, under Vatican rules, members of the clergy must offer to resign when they reach that age.
The Most Reverend Dr Dermot Farrell, until now Bishop of Ossory, has been appointed his successor.
He is also a former President of St Patrick's College and the National Seminary at Maynooth.
File image: Archbishop of Dublin, Diarmuid Martin