Triest was born in Brussels, the ninth of 14 children of Jan and Cecilia Mello Triest. His father was a blacksmith and ironmonger. Petrus was educated at the Jesuit College of St Michael and then at the Latin school in
Geel.
Saint Dymphna, patron saint of the mentally ill, is particularly honoured in Geel, the site of her martyrdom. He obtained the degree of Bachelor of Philosophy from the
University of Louvain, then entered the
Major Seminary, Mechelen, and was ordained priest in 1786 by
Cardinal de Frankenberg. As a seminarian he was noted for his devotion to the
Sacred Heart and great compassion for the needy and sick. He was made vicar of
Hanswijk in Mechelen in 1792. In 1795 Triest caught typhus while tending the sick during an outbreak at the military hospital, but he recovered. When Belgium was annexed to France in 1795, Triest refused the
Republican Oath and went into hiding. For some months, he was only able to administer the sacraments clandestinely. After giving
viaticum to the dying wife of a brigadier of gendarmes, he received a private assurance that he would not be arrested. Triest was made
Canon of the Chapter of
St Bavo's Cathedral and served on the Almhouses Commission. Triest sent a small group of brothers to
Froidmont to work at the psychiatric hospital of Saint Charles. In 1825, they opened a school for deaf boys in Ghent. Triest died 24 June 1836 in Ghent. He was buried in the parish cemetery at Lovendegem with a modest tombstone. In 1846 the government installed a marble memorial in
Brussels Cathedral. == Honours ==