Archbishop of Dublin Diarmuid Martin is expected to mark his 75th birthday today by offering his resignation to Pope Francis.
According to the Catholic Church's Code of Canon Law, diocesan bishops are requested to offer their resignations to the pope when they turn 75.
However, it does not signal an automatic or immediate retirement.
The resignation requirement emerged during the Second Vatican Council.
The council's 1965 decree on the pastoral office of bishops, Christus Dominus, did not specify a mandatory retirement age, but "earnestly requested" prelates to offer their resignation if "the increasing burden of age or some other serious reason" made them "less capable of fulfilling their duties".
In 1983, the age requirement was added to canon law.
Indications are that the Archbishop of Dublin, who is currently in isolation due to Covid-19, will remain in the role for some time.
In a message of hope marking the beginning of Holy Week last weekend, Archbishop Martin said it is the first year in his 50 years of ministry, that he will be unable to participate in or lead Easter services due to restrictions around the coronavirus.
Born in Dublin in 1945, Archbishop Martin was ordained a priest on 25 May 1969. He succeeded Cardinal Desmond Connell as Archbishop of Dublin in April 2004.
