The Bishop of Raphoe, Philip Boyce, is being investigated by the Director of Public Prosecutions after being accused of inciting hatred in a homily he delivered at Knock shrine.
The complaint was made by former Fine Gael election candidate and atheist John Colgan, who said that the address by Dr Boyce was in breach of the Prohibition of Incitement to Hatred Act, 1989, according to the Irish Independent.
The homily, entitled: "To Trust in God" was delivered to worshippers during a novena at the Marian shrine in Co Mayo last August.
Colgan referred in his formal complaint to two key passages in Boyce's homily which he believes broke the law.
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One of the passages referred to the Catholic Church in Ireland being "attacked from outside by the arrows of a secular and godless culture."
A second passage stated: "For the distinguishing mark of Christian believers is the fact they have a future; it is not that they know all the details that await them, but they know in general terms that their life will not end in emptiness."
In his complaint Colgan, who was a leader in the 'Campaign to Separate Church and State' in the late 1990s," said: I believe statements of this kind are an incitement to hatred of dissidents, outsiders, secularists, within the meaning of the [Incitement to Hatred] Act, who are perfectly good citizens within the meaning of the civil law. The statements exemplify the chronic antipathy towards secularists, humanists etc, which has manifested itself in the ostracising of otherwise perfectly good Irish citizens, who do not share the aims of the Vatican's Irish Mission Church."
Martin Long of the Catholic Communications office made a statement to the Sunday Independent, saying: "Bishop Boyce's homily 'To Trust in God' is available for anyone to read at catholicbishops.ie.
"I advise any person to read it and judge it for themselves. It is clearly a reasonable, balanced, honest -- and indeed self-critical from a church perspective -- analysis of the value of the Catholic faith. Bishop Boyce is a good and holy man and much loved by those who know him."
After the homily was delivered last summer, Colgan wrote to the cleric seeking a corrective statement.
In his response, Boyce said that that in his homily he did "not wish to disparage in any way the sincere efforts of those with no religious beliefs, atheists, humanists etc.
"I have too much respect for each human person, since I believe all are created in the image of God. At Knock I wished to encourage and confirm the hope of believers, even in the present challenging times, since trust in God was the theme I was given."