Father Eugene O’Hagan has been having another tough week. The organ at the Church of the Sacred Heart is broken and his attempts to make his iPod work for the All Souls Mass came to naught.

But next week he can forget his troubles as a priest in a small Roman Catholic parish in Northern Ireland for at least one night. On Tuesday he will be singing alongside his brother, Father Martin O’Hagan, and an old schoolfriend, Father David Delargy, in Liverpool’s Catholic Cathedral.

Nothing unusual in that: three musical priests who have been singing together for 30 years giving a concert. Except that in the past year the Priests have become an award-winning, record-breaking global success story, their first album going platinum in the UK and Ireland and sales of 1.3 million around the world.

It’s a safe bet that Father O’Hagan won’t be needing his iPod. The trio will be supported by a full orchestra and the concert is being filmed by PBS for broadcast across the United States.

They will be singing from their new album, Harmony, released later this month. You’ll Never Walk Alone features, as does King of Kings, a “hymn with a modern twist” written by the trio. It’s the same formula as the Priests’ eponymous debut album, except that Father O’Hagan, 50, thinks that it benefits from the intense singing of the past year.

“We’ve been performing in Stockholm, Paris, Madrid, New York and Washington in very focused spikes of activity,” says the priest, whose regular audience is a parish of just 350 Catholics in the staunchly Protestant town of Ballyclare, Co Antrim.

All three insist that “the day job” remains their first priority, never allowing their commitments to a £2 million, four-album deal to come before their parish work. Their contract with Epic, a subsidiary of Sony, stipulates that they will never be asked to put record promotion ahead of their duties.

Life has changed, of course. It has become busier. Father O'Hagan has to juggle daily Mass, visiting the sick and elderly, and sitting as a judge in Belfast to decide on marriage annulments. After meeting those commitments he hops on planes around the world.

“Our longest period away was when we went to Sydney but there was also a tour of America. I’m lucky in that a retired priest came up to give Mass while I was away, but Martin has just moved to a much larger parish and we shall have to wait and see how that works out.”

They are also suddenly rich. “We are always talking about people resisting temptation and now we will have to practise what we preach,” said Father O’Hagan. "When this began we didn’t realise we would be so successful. So we are in the process of establishing our own charity and into that trust we will be putting a significant share of the royalties.”

They intend to donate to Shelter in the UK and the Simon Community in Ireland, as well as providing financial support for a school in Cambodia run by the Mercy Sisters, another school in Kampala run by Presbyterians, and a project for street children in Thailand.

“There’s also a bit of charity beginning at home because we will be giving money to support retired and sick priests of our own diocese. There have been a lot of unsung heroes during the Troubles here.”

Having sung for Pope John Paul II, the Queen and the Prince of Wales, The Priests hope they will get an opportunity to sing for Benedict XVI next year when he visits Britain.

Father O'Hagan says that while there has been no official feedback from the Vatican about the commercial success of The Priests, their Diocesan bosses have been supportive.

“I wondered how they would view this at the beginning. They might have said, ’Well who are they and what do they think they are doing?’. But I think by this stage all the questions have been answered.

“We’ve always experienced our music as a great bridge, it’s something very positive. And we are very obviously priests: the dog collar is a dead giveaway. Many Catholics have been encouraged by the fact that we wear our dog collars and are who we say we are.”

“Our goal is to lift people’s hearts. The music might lighten people’s burdens in these dull days of recession. The success is welcome and more than we expected, but nobody can accuse us of peaking too soon.”

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