The increasing liberalisation of Irish society coupled with a sharp decline in the numbers of young people becoming priests, brothers and nuns have contributed to that erosion over the past 30 years. But it has been hastened by several scandals, all of which touch on sexual morality.
The discovery in 1992 that Bishop Eamonn Casey of Galway fathered a child 20 years ago was the first in a series of embarrassing disclosures. Last month a priest who was found guilty of child sexual abuse was indirectly responsible for the break-up of the government because an extradition warrant from Northern Ireland for his arrest had been in the Attorney-General's office in Dublin for seven months without any action.
Around the same time another priest died in a gay club in Dublin where he reportedly received the last sacraments from two other regular priest visitors to the club. And barely a week goes by without one or more allegations of sexual abuse against priests and nuns in educational or other Church-linked establishments.
The bishops are patrons of the majority of primary schools and legally responsible for them. Last month 20 former pupils of one school announced that they are to sue the bishop patron of the school as well as the education ministry and a teacher over alleged abuse. If they are successful a series of other claims may follow, many reviving incidents years old.
Most commentators are agreed that the scandals have weakened the authority of the Church when it comes to matters of morality, particularly on sexual issues. But now publicity is beginning once again to focus on schools, the vast majority of which are Church-linked.
One critic has suggested that the scandals are bound to affect the Church's position in schools where its influence is still very considerable. But others are not so sure. A leading Church spokesman said: "There will be Catholic schools as long as the parents want them."
He may well be right, but a debate broadcast this week on RTE's The Davis Show revealed that, while Irish parents want Church-linked schools, they also want a greater say in running them.
Church representatives on the programme were adamant that the only way to ensure the ethos and character of the schools was by the Church itself having effective voting majorities on the management boards. But the National Parents' Council and teacher unions want parents and teachers to share equal representation with the Church.
The previous Education Minister Niamh Bhreathnach tried unsuccessfully to get both Catholic and Protestant leaders to agree to this. The Catholics claimed that she had a secularist agenda and wanted to drive the Church out of schools. It remains to be seen whether the approach of the new government will prove more acceptable.
The present spate of scandals will blow over - the Irish people and the Catholic Church will have to come to terms with the spotlight falling on issues that have traditionally remained hidden.
But the series of incidents, along with other factors such as lack of new recruits, ageing priests and nuns, more lay school heads, the calls for greater democracy in the church and in schools will all combine to reduce the power of the Church and its control over Irish education. The Catholic Church will still be a force in education for years to come, but no longer the dominant force that it once was.