During other sermons on the theme of repentance, Serra would hoist a large stone in one hand and, while clutching a crucifix in the other, smash the stone against his chest. Many of his listeners feared that he would strike himself dead. Later, Serra suffered chest pains and shortness of breath; Palóu suggests that Serra's self-inflicted bruises were the cause. While preaching of hell and damnation, Serra would sear his flesh with a four-pronged candle flame—emulating a famed Franciscan preacher, John of Capistrano. Palóu described this as "quite violent, painful, and dangerous towards wounding his chest."