Eisenmenger before his death, and his heirs after him, knowing that the king of Prussia was inclined to listen to accusations against the Jews, had applied to him to entreat Emperor Leopold to release the book against the Jews, entitled "Judaism Unmasked," from ban and prohibition. Frederick I interested himself warmly in the matter, and sent a kind of petition to Emperor Leopold I (April 25, 1705) very characteristic of the tone of that time. The king represented that Eisenmenger had sunk all his money in this book, and had died of vexation at the imperial prohibition. It would seem a lowering of Christianity if the Jews were so powerful as to be able to suppress a book written in defense of Christianity and in refutation of Jewish errors. There was no reason to apprehend, as the Jews pretended, that it would incite the people to a violent onslaught against them, since similar writings had lately appeared which had done them no harm. Eisenmenger's book aimed chiefly at the promotion of Christianity, so that Christians might not, as had repeatedly happened some years ago, be induced to revolt from it and become adherents of Judaism. But Emperor Leopold would not remove the ban from Eisenmenger's book. King Frederick repeated his request three years later, at the desire of Eisenmenger's heirs, to Emperor Joseph I. With him also King Frederick found no favorable hearing, and the 2,000 copies of "Judaism Unmasked" remained at Frankfort under ban for forty years. But with Frederick's approval a second edition was brought out at Königsberg, where the imperial censorship had no power. For the moment it had no such effect as the one side had hoped and the other feared; but, later on, when the rights of Jews as men and citizens were considered, it proved an armory for malicious or indolent opponents.
King Frederick I was often urged by enemies of the Jews to make his royal authority a cloak for their villainy. The bright and the dark side of the general appreciation of Jewish literature appeared clearly. In Holland, likewise a Protestant country, a Christian scholar of this period cherished great enthusiasm for the Mishna, the backbone of Talmudical Judaism. William Surenhuysius, a young man of Amsterdam, in the course of many years translated the Mishna with two commentaries upon it into Latin (printed 1698-1703). He displayed more than the usual amount of Dutch industry and application. Love certainly was needed to undertake such a study, persevere in it, and finish the work in a clear and attractive style. No language and literature present so many difficulties as this dialect, now almost obsolete, the objects which it describes, and the form in which it is cast. Surenhuysius sat at the feet of Jewish teachers, of whom there were many at Amsterdam, and he was extremely grateful for their help. But their assistance did not enable him to dispense with industry and devotion. He was influenced by the conviction that the oral Law, the Mishna, in its main contents is as divine as the written word of the Bible. He desired that Christian youths in training for theology and the clerical profession should not yield to the seductions of classical literature, but by engaging in the study of the Mishna should, as it were, receive ordination beforehand.