Bishop of Cork and Ross, Dr John Buckley, explored the issues surrounding the controversial topic in a pastoral letter read out at all weekend Masses in the diocese.
The bishop said abortion to end the life of an unborn child was "gravely wrong in all circumstances" but differed from medical treatments to "save the mother" which do not intentionally seek to end the life of an unborn baby.
The bishop said the current legislation and medical guidelines allow nurses and doctors in Irish hospital to apply this "vital distinction" in practice.
"Contrary to what has been widely said, the judgment of the European Court of Human Rights does not oblige the Irish Government to legislate for abortion," he said.
Dr Buckley said the Lisbon Treaty was passed on the second attempt following assurances that Ireland had the right to determine its own policies on abortion.
He said three of the four options put forward by the Government-appointed expert group involve abortion and could "never be morally justified".
He said one of the options involved, the drawing up of enhanced medical guidelines to ensure consistency in the delivery of medical treatment, could be a "way forward".
"International statistics confirm that Ireland, without abortion, remains one of the safest countries in the world in which to be pregnant and to give birth," Dr Buckley said.
Innocent
He added that the child in the womb was entitled to the same rights as all others, including the "right of an innocent person to life".
However, in the letter, he also pointed out that society had a responsibility to "defend and promote the equal right to life of a pregnant mother and the innocent and defenceless child in her womb" when either of their lives are at risk.
"They have an equal right to life," he wrote. "The Catholic Church has never taught that the life of a child in the womb should be preferred to that of the mother."
He said medical interventions were "morally permissible" in situations where a seriously ill pregnant woman needs medical treatment which may put the life of her baby at risk, after every effort had been made to save both.