One of the most prominent reasons urged for the establishment and perpetuation of the Inquisition was the zeal of the crypto-Jews in proselyting and the danger to which the purity of religion was thus exposed--an argument which served its purpose, however discrediting to the firmness of Spanish faith. Cases, however, were never cited in proof, nor could they be, for Judaism is a matter of race as much as of dogma; the Jews have never sought to convert the Gentiles and, in Spain of all lands, it was clearly preposterous that men, who could only exist by concealing their belief, would incur the certainty of detection and of pitiless punishment, by the unpardonable offence of seeking the apostasy of their Christian neighbors. What conversions there were were spontaneous, and these served to intensify the horror of Judaism and to keep alive the sense of danger arising from the presence of those suspected of cherishing the ancient faith. Fray Diogo da Assumpçao, burnt in Lisbon, in 1603, as a convert to the Law of Moses, is said to have been led to this fatal step by witnessing the constancy in martyrdom of those who suffered for their belief.[805] A more remarkable case was that of Lope de Vera, which aroused universal interest throughout Spain, and pointed the moral that the safety of religion lay in the ignorance of the faithful, thus justifying the prescience of Valdés, when he placed on the first Spanish Index a translation of Josephus's Antiquities of the Jews.[806] Lope de Vera was the son of a gentleman of San Clemente, of gentle blood and limpieza. At the age of nineteen he was a student at Salamanca, so deeply learned in Hebrew and Arabic that, in July, 1638, he competed for a chair of Hebrew. His studies led him to embrace Judaism and, with the zeal of a convert, he sought to win over a fellow student, who denounced him to the Inquisition. There was a second witness, and yet the consulta de fe of Valladolid was not unanimous in voting his arrest; it had to be ordered by the Suprema, and was executed June 24, 1639. He freely admitted the truth of the accusation and much more, but denied intention, assuming that what he had said was for the sake of argument, and asserting that he went to confession and communion and carried a rosary. There was variation and equivocation in his successive audiences; there was delay and doubt on the part of the Inquisition, and the trial dragged on. On April 16th and May 23, 1641, he revoked all that he had confessed and then suddenly, on May 29th, he announced that he wished to be a Jew and to hold all that the Jews believed, for this was the truth revealed to them by God, which he would defend with his life. Hitherto he had believed what the Church taught, but now he adhered to the Law given by God to Israel; the religion of Rome and all other religions were false; he had never practised the Jewish observances but would do so in the future; no one had taught him this,