This attack furnished Wycliffe with a model for his onslaught. In his earlier days he had treated the Friars with respect and even as allies--"a Franciscan" he had said, "is very near to God"--for then he had been attacking the endowments of the Church, and it was the monks or "possessioners" and the rich secular clergy to whom he was opposed. In theory the Mendicant Orders were opposed to these by their poverty and in practice by their interests. But the Friars were the close allies and chief defenders of the Pope. Now, therefore, when Wycliffe passed from political to doctrinal reform, his attitude towards the Mendicant Orders becomes one of uncompromising hostility. He and his followers denounced them with all the vehemence of religious partisanship and all the vigour of the vernacular. Iscariot's children, they called them, and irregular Procurators of the Fiend, adversaries of Christ and Disciples of Satan. Wycliffe indeed went so far as to attribute an outbreak of disease in Oxford to the idleness and intellectual stagnation of the Friars. "Being inordinately idle and commonly gathered together in towns they cause a whole sublunary unseasonableness." Finally, Wycliffe aimed at undermining the power of the priesthood by challenging the doctrine of Transubstantiation. According to this doctrine the priest had the power of working a daily miracle by "making the body of Christ." Wycliffe, in the summer of 1381, first publicly denied that the elements of the sacrament underwent any material change by virtue of the words uttered by the priest. The real presence of the body and blood of Christ he maintained, but that there was any change of substance he denied.