Leo Varadkar offered his support to Fr Oliver O'Reilly from Ballyconnell parish.
Fr O'Reilly previously described a "long reign of terror" hanging over the Cavan-Fermanagh area and urged those involved to end the violence.
The Taoiseach said: "In his homily following the vicious assault on Kevin Lunney, Fr O'Reilly spoke from the heart and the head, and offered leadership to a distressed community.
"He offered moral guidance to his community, he condemned the savagery of the kidnapping and the ongoing campaign of intimidation, and called on everyone to co-operate with the authorities.
"I believe that Fr O'Reilly showed considerable courage in giving this homily and I commend him for doing so."
It was reported over the weekend that one of Fr O'Reilly's parishioners, the businessman Sean Quinn, has written to the Vatican to complain.
The Quinn family have consistently condemned and distanced themselves from those attacking the new owners.
Mr Lunney, 50, a director of Quinn Industrial Holdings (QIH), was snatched near his Co Fermanagh home and brutally assaulted in September.
The father of six spoke out about the attack in a BBC Spotlight interview, describing how he had been slashed with a knife, doused with bleach and branded by his captors before being dumped on a remote road in Co Cavan.
Criminals targeting QIH executives are believed to have been behind the attack.
A cross-border police investigation is under way.
Mr Varadkar met the directors of Quinn Industrial Holdings earlier this month.
The attack, during which his assailants demanded Mr Lunney's resignation, was the most serious in a five-year campaign of intimidation targeting the companies and directors that now control the business portfolio which was built up by fallen tycoon Sean Quinn, once Ireland's richest man.
A series of police searches connected with the investigation into the attack on Mr Lunney were carried out near the Irish border and one at an address in the Buxton area of Derbyshire.
A man died during the Derbyshire Police raid - Cyril McGuinness - known as Dublin Jimmy. It is believed he had a heart attack.
The Independent Office for Police Conduct (IOPC) has launched an inquiry into the circumstances of the death.
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