When he was not preaching, John was writing tracts against heresy of every kind. This facet of his life is covered in great detail by his early biographers, Nicholas of Fara, Christopher of Varese and Girlamo of Udine. While he was thus evangelizing, he was actively engaged in assisting Bernardine of Siena in the reform of the Franciscan Order, largely in the interests of a more rigorous discipline in the Franciscan communities. Like Bernardine, he strongly emphasized devotion to the Holy Name of Jesus, and, together with that saint, was accused of heresy on this account. In 1429, these Observant friars were called to Rome to answer charges of heresy, and John was chosen by his companions to speak for them. They were both acquitted by the Commission of Cardinals appointed to judge the accusations.