Jacobus was educated at the Cistercian Abbey of Boneffe in the County of Namur. He studied philosophy at Louvain University, and graduated magister artium on 27 March 1553.
For the next nine years he was a student of theology in Pope's College, Leuven, following the lectures of Ruard Tapper and Josse Ravestein. After graduating Bachelor of Sacred Theology he continued his studies at the Sorbonne.