His Manual of Catholic Devotions was used in revised form by the armed forces during World War II.
Gahan had studied at Louvain, Belgium to the doctorate level. In 1761 he began parish work in Dublin.
He was once jailed for refusing to break the seal of sacramental Confession. Twice he was Provincial of the Order in Ireland.
After centuries in hiding, the Order in Ireland became stronger after some toleration of religious liberty by the Emancipation Act of 1828.
During the rest of that nineteenth century, Augustinian communities were set up once again in a few of the twenty towns where they previously had existed.
Over the years these Irish Augustinian communities in the late nineteenth century gained enough candidates and became sufficiently established to receive successively from the Curia of the Order in Rome full recognition as an official house of the Order.
(In Latin, this was a domus formata - a house formed according to all requirements and regulations of the Church and the Order).
Augustinians from Ireland brought the Order back to England and formed a community at Hoxton in London in 1864.
In 1862 there began the construction of a great church at Saint John's Lane in Dublin, which was completed externally in 1895 and internally in 1911.
In 1878 Irish candidates to the Order were sufficient to open a house of study in Orlagh, near Dublin.
In 1883 there were fifty-three priests in the Irish Province, and the responsibility was accepted to staff a vicariate in North Queensland, Australia.
A similar responsibility was taken on regarding the north of
Nigeria in Africa in 1938.
The houses in Nigeria became a Vice-Province in 1997 and a separate Province of Nigeria in 2001.
The Irish Province has more than a dozen communities in Ireland, and a community overseas at Saint Patrick's Church (Rome, Italy) - see link below.
Some of its members still minister in Augustinian ministries in
Australia, Ecuador and
Nigeria, and a number of individuals have special ministries elsewhere.
Photos (at right)
Students from Saint Augustine's College, Dungarvan, Ireland. They were photographed during an excursion to France.