The king, well aware of the origin and object of these accusations, had them thoroughly sifted, with the result that the innocence of the accused was completely established. Notwithstanding this fact, the enemies of the Jews maintained their guilt. Some insinuated that the judges had been bribed; while others asserted that the new-Christians had exerted themselves in behalf of their kinsmen, and that the king himself was partial to them. Among all their enemies the man who raged most bitterly and fiercely against the Spanish Jews was a preacher in Salamanca, Alfonso de Spina, a Franciscan monk, of the same order and opinions as Capistrano. Instead of the venomed tongue, he used the poisoned pen against them. This man enjoyed a certain amount of fame, because he happened to have accompanied Alvaro de Luna, the once all-powerful minister of John II, to the scaffold as his confessor. This bigoted priest thundered unceasingly from the altar steps against the Jews and their patrons, and especially against the new-Christians as secret adherents of their former faith. As his preaching did not appear to him to produce sufficient effect, De Spina issued, in 1460, a virulent work in Latin, directed against Jews, Moslems, and other heretics, under the title "Fortalitium Fidei." In this book he collected everything that the enemies of the Jews had ever written or said against them. He reproduced every absurd legend and idle tale that he could procure, and seasoned the whole collection with every device of rhetoric that his malice could suggest. In his opinion it was only right and natural that all Moslems and heretics should be exterminated root and branch. Against the Jews, however, he proposed to employ apparently lenient measures. He would simply take their younger children from them, and bring them up as Christians, an idea for which he was indebted to the scholastic philosopher, Duns Scotus, and his fellow Franciscan, Capistrano. De Spina most deeply deplored that the various laws for the persecution of the Jews, promulgated during the minority of John II, were no longer in force under his successor. In most trenchant words he rebuked the king, the nobles and the clergy for the favor that they showed to Jews; and, in order to inflame the mob, he untiringly retailed all the old fables of child-murder, theft of the host, and the like, in the most circumstantial narrative, and insinuated that the partiality of the king permitted these abominable crimes to go unpunished.