He was appointed to teach philosophy in the same college, where he continued his course of theology, under the professors, Ruard Tapper and Jan Hessels (also known as Jean Leonardi Hasselius).
Arrived at Trent in September 1551, with his four colleagues from the University of Leuven, he presented in November a memorandum "super articulis de sacramentis poenitentiae at extremae unctionis".
Called by Ferdinand I to the Conference of Worms in 1557, he accompanied Franciscus Sonnius and Martin Rythovius and there met three other theologians from the Low Countries: Jean Delphinus, Barthélemy Latomus, and Peter Canisius.
Through his efforts the teachings of the innovator Michel Baius were censured by the Spanish Universities of Salamanca and Alcalá, by the Faculty of Paris in 1560, and by Pius V in his Bull "Ex omnibus afflictionibus" of 1 October 1567.
Patri Laurentio Villavincentio", against Baianism; "Demonstratio religionis christianae ex verbo Dei"; "Confessionis, sive doctrinae, quae nuper edita est a ministris qui in ecclesiam Antverpiensem irrepserunt et Augustanae confessioni se assentiri profitentur succincta confutatio"; "Apologia Catholicae confutationis profanae illius et pestilentis confessionis, quam contra inanes cavillationes Matthaei Flacci Illyrici"; "De concordia gratiae et liberi arbitrii"; "Epistolae tres Michaeli de Bay"; "Apologia seu defensio decretorum concilii Tridentini de sacramentis adversus censuaras et examen Martini Kemnitii" in two parts.