Originally a licentious soldier and brigand, Gerlache became a pious Christian upon the death of his wife and went on pilgrimage to Rome and Jerusalem.

Upon returning to the Netherlands, he gave up all of his possessions to the poor and took up residence in a hollow oak on his former estate near Houthem.

[2] He ate bread mixed with ash and traveled by foot each day on pilgrimage to Maastricht, to the Basilica of Saint Servatius.

Gerlach, however, had by this time made powerful friends, including Hildegard of Bingen, and received protection.

Legend states that when Gerlach had done enough penance, water from the local well transformed itself into wine three times as a sign that his sins had been forgiven.

Contributors to the project included Charlie Watts and Ron Wood of The Rolling Stones who had a guided tour of the church and museum while staying at the Chateau during a concert in Landgraaf in June 2014.