Moral cleanness is indelibly stamped upon hundreds of pages of Luther's writings. The Sixth Commandment in its wider application to the mutual relation of the sexes and the sexual condition of the individual was to Luther the solemn voice of God by which the holy and wise Creator guards and protects the fountains whence springs human life. "Because there is among us," he says, "such a shameful mixture and the very dregs of all kinds of vice and lewdness, this commandment is also directed against all manner of impurity, whatever it may be called; and not only is the external act forbidden, but every kind of cause, incitement, and means, so that the heart, the lips, and the whole body may be chaste and afford no opportunity, help, or persuasion for impurity. And not only this, but that we may also defend, protect, and rescue wherever there is danger and need; and give help and counsel, so as to maintain our neighbor's honor. For wherever you allow such a thing when you could prevent it, or connive at it as if it did not concern you, you are as truly guilty as the one perpetrating the deed. Thus it is required, in short, that every one both live chastely himself and help his neighbor do the same." (_Large Catechism_, p. 419.) The reason why God in the Sixth Commandment refers to only one form of sexual impurity Luther states correctly thus: "He expressly mentions adultery, because among the Jews it was a command and appointment that every one must be married. Therefore also the young were early married, so that the state of celibacy was held in small esteem, neither were public prostitution and lewdness tolerated as now. Therefore adultery was the most common form of unchastity among them." (_Ibid_.) In his _Appeal to the German Nobility_ Luther says: "Is it not a terrible thing that we Christians should maintain public brothels, though we all vow chastity in our baptism? I well know all that can be said on this matter; that it is not peculiar to one nation, that it would be difficult to demolish it, and that it is better thus than that virgins, or married women, or honorable women should be dishonored. But should not the spiritual and temporal powers combine to find some means of meeting these difficulties without any such heathen practise? If the people of Israel existed without this scandal, why should not a Christian nation be able do so? How do so many towns and villages manage to exist without these houses? Why should not great cities be able to do so? . . . It is the duty of those in authority to see the good of their subjects. But if those in authority considered how young people might be brought together in marriage, the prospect of marriage would help every man and protect him from temptations." (10, 349; transl. by Waring.) This is the Luther of whom Catholic writers say that he would not be considered qualified to sit with a modern Vice Commission.