divorce, though he did not forbid it, and recommended that a man should rather have a plurality of wives than that he should put away any of them. Luther held strenuously the view that marriage was a purely external contract for the purpose of sexual satisfaction, and in no way entered into the spiritual life of the man. On this ground he sees no objection in the so-called mixed marriages, which were, of course, frowned upon by the Catholic Church. In his sermon on "Married Life" he says: "Know therefore that marriage is an outward thing, like any other worldly business. Just as I may eat, drink, sleep, walk, ride, buy, speak and bargain with a heathen, a Jew, a Turk or a heretic; so may I also be and remain married to such an one, and I care not one jot for the fool's laws which forbid it.... A heathen is just as much man or woman, well and shapely made by God, as St. Peter, St. Paul, or St. Lucia." Nor did he shrink from applying his views to particular cases, as is instanced by his correspondence with Philip von Hesse, whose constitution appears to have required more than one wife. He here lays down explicitly the doctrine that polygamy and concubinage are not forbidden to Christians, though, in his advice to Philip, he adds the _caveat_ that he should keep the matter dark to the end that offence might not be given; "for," says he, "it matters not, provided one's conscience is right, what others say". In one of his sermons on the Pentateuch[10] we find the words: "It is not forbidden that a man have more than one wife. I would not forbid it to-day, albeit I would not advise it.... Yet neither would I condemn it." Other opinions on the nature of the sexual relations were equally broad; for in one of his writings on monastic celibacy his words plainly indicate his belief that chastity, no more than other fleshly mortifications, was to be considered a divine ordinance for all men or women. In an address to the clergy he says: "A woman not possessed of high and rare grace can no more abstain from a man than from eating, drinking, sleeping, or other natural function. Likewise a man cannot abstain from a woman. The reason is that it is as deeply implanted in our nature to breed children as it is to eat and drink."[11] The worthy Janssen observes in a scandalised tone that Luther, as regards certain matters relating to married life, "gave expression to principles before unheard of in Christian Europe;"[12] and the British Nonconformist of to-day, if he reads these "immoral" opinions of the hero of the Reformation, will be disposed to echo the sentiments of the Ultramontane historian.