After the monks had arrived in Roscrea in 1878, the first thing thsy set about doing was building a monastic Church. Work began in 1879 and but 1882 the church was build and the first Mass had been said in it. It was not until 1884 that the Church was completed and consecrated, an even attended by 10,000 people.

For the last one hundred and twenty years this church has remained the centre of monastic life at Roscrea. It is here that the monks gather seven times a day for the office and the Mass.

It is here that the young monk makes his commitment to God in his Solemn Profession of monastic vows, and it is from here that the monk is taken at the end of his life to be buried in the cemetery.

The Tower on the church was build between 1934 and 1936. There are two bells in the tower that ring to announce the different offices throughout the day and to mark the different periods of the day. They are named Ciaran and Cronan after two early Irish monastic saints.

Originally the church was divided in two with one section for monks and another for visitors and guests. Since the late 1970s the partition has been removed and the whole church is open to all.

The nave of the church is dominated by the Choir of 80 stalls which is the area used by the monks for the Opus Dei and Eucharist.