Jan was taught the tailoring handicraft at Leyden, but seems to have received little schooling.

His natural abilities, however, were considerable, and he eagerly devoured the religious and propagandist literature of the time.

Amongst other writings the pamphlets of Thomas Muenzer especially fascinated him.

He travelled a good deal, visiting Mechlin and working at his trade for four years in London.

Returning home, he threw himself into the Anabaptist agitation, and, scarcely twenty-five years old, he was won over to the doctrines of Jan Matthys.