He was an extremely popular preacher because he spoke simply and powerfully against the vanity, ambition and greed rife at the time. The crowds that flocked to hear him were too large for the local churches, so he addressed them in the city squares and the fields. Like many other missioners of his century, he had made a vast outdoor bonfire called "burning the Devil's stronghold". The crowds were asked to throw into the fire all objects of vanity and sin such as playing cards, dice, pornographic books and pictures, jewelry, wigs, superstitious charms, cosmetics, and so forth.