Influenced by the teaching of the French school and St. Francis de Sales, especially as set out in the Treatise on the Love of God, and also by the revelations of St. Gertrude and St. Mechtilde, he was the theoretician, so to speak, of devotion to the Sacred Heart and explained the expressions of his predecessors.
On January 25, 1299, he married Mechtilde of Arenberg (died March 18, 1328), daughter of Johann of Arenberg and Katharina of Jülich.