During his residence in Naples, Valla delivered public lectures on eloquence, which were attended by crowded audiences. But the imprudence of his zeal in the correction of vulgar errors in matters of theological belief again involved him in dangers and difficulties. He appears to have possessed that superiority of intellect above his contemporaries, which, when united to a warm temper and a propensity to disputation, never fails to draw down upon the inquisitive the hatred of fanaticism. In the pride of superior knowledge, he provoked the indignation of the bishop of Majorca, by asserting that the pretended letter of Christ to Abgarus was a forgery.[427] In aggravation of this heresy, he had moreover derided the assertion of a preaching friar, who had inculcated upon his audience the commonly received notion, that the formulary of faith, generally known by the name of the apostles’ creed, was the joint composition of those first heralds of salvation.[428] The freedom with which he descanted upon these delicate topics of dispute exposed him to the utmost peril. His enemies publicly arraigned him before a spiritual tribunal, where he underwent a strict examination; and it is very probable, that had not Alfonso interposed the royal authority on his behalf, not even a recantation of his imputed errors would have saved him from the severe punishment which the atrocity of religious bigotry has allotted to those who deviate from the narrow line of orthodox faith.[429] Theology was not the only subject of investigation which involved Valla in altercation and strife. Literary jealousy kindled the flame of hostility between him and Beccatelli, whom he attacked in a violent invective. With Bartolomeo Facio also he maintained a controversy, in the course of which he manifested the utmost bitterness of spirit.[430]