The battle between the Turks and the Christians, in the 16th century scourge sent by God to punish Christians, as agents of the Biblical apocalypse that would destroy the antichrist, whom Luther believed to be the papacy, and the Roman
Church.[176] He consistently rejected the idea of a Holy War, "as though our people were an army of Christians against the Turks, who were enemies of Christ. This is absolutely contrary to Christ's doctrine and name".[177]
On the other hand, in keeping with his doctrine of the two kingdoms, Luther did support non-religious war against the Turks.[178] In 1526, he argued in Whether Soldiers can be in a State of Grace that national defence is reason for a just war.[179] By 1529, in On War against the Turk, he was actively urging Emperor Charles V and the German people to fight a secular war against the Turks.[180]
He made clear, however, that the spiritual war against an alien faith was separate, to be waged through prayer and repentance.[181] Around the time of the Siege of Vienna,
Luther wrote a prayer for national deliverance from the Turks, asking God to "give to our emperor perpetual victory over our enemies".[182]
In 1542, Luther read a Latin translation of the Qur'an.[183] He went on to produce several critical pamphlets on Islam, which he called "Mohammedanism" or "the Turk".[184] Though Luther saw the Muslim faith as a tool of the devil, he was indifferent to its practice: "Let the Turk believe and live as he will, just as one lets the papacy and other false Christians live."[185] He opposed banning the publication of the Qur'an, wanting it exposed to scrutiny.[186]
Antinomian controversy Early in 1537, Johannes Agricola (1494–1566) – serving at the time as pastor in Luther's birthplace, Eisleben – preached a sermon in which he claimed that God's gospel, not God's moral law (the Ten Commandments), revealed
God's wrath to Christians. Based on this sermon and others by Agricola, Luther suspected that Agricola was behind certain anonymous antinomian theses circulating in Wittenberg. These theses asserted that the law is no longer to be taught to Christians but belonged only to city hall.[187] Luther responded to these theses with six series of theses against Agricola and the antinomians, four of which became the basis for disputations between 1538 and 1540.[188] He also responded to these assertions in other writings, such as his 1539 open letter to C. Güttel
Against the Antinomians,[189] and his book On the Councils and the Church from the same year.[190] In his theses and disputations against the antinomians,
Luther reviews and reaffirms, on the one hand, what has been called the "second use of the law," that is, the law as the Holy Spirit's tool to work sorrow over sin in man's heart, thus preparing him for Christ's fulfillment of the law offered in the gospel.[191] Luther states that everything that is used to work sorrow over sin is called the law, even if it is Christ's life, Christ's death for sin, or God's goodness experienced in creation.[192] Simply refusing to preach the Ten Commandments among Christians – thereby, as it were, removing the three letters la-w from the church – does not eliminate the accusing law.[193] Claiming that the law – in any form – should not be preached to Christians anymore would be tantamount to asserting that Christians are no longer sinners in themselves and that the church consists only of essentially holy people.[194]
On the other hand, Luther also points out that the Ten Commandments – when considered not as God's condemning judgment but as an expression of his eternal will, that is, of the natural law – also positively teach how the Christian ought to live.[195] This has traditionally been called the "third use of the law."[196] For Luther, also Christ's life, when understood as an example, is nothing more than an illustration of the Ten Commandments, which a Christian should follow in his or her vocations on a daily basis.[197]
The Ten Commandments, and the beginnings of the renewed life of Christians accorded to them by the sacrament of baptism, are a present foreshadowing of the believers' future angel-like life in heaven in the midst of this life.[198] Luther's teaching of the Ten Commandments, therefore, has clear eschatological overtones, which, characteristically for Luther, do not encourage world-flight but direct the Christian to service to the neighbor in the common, daily vocations of this perishing world.
Bigamy of Philip of Hesse From December 1539, Luther became implicated in the bigamy of Philip I, Landgrave of Hesse, who wanted to marry one of his wife's ladies-in-waiting. Philip solicited the approval of Luther, Melanchthon, and Bucer, citing as a precedent the polygamy of the patriarchs. The theologians were not prepared to make a general ruling, and they reluctantly advised the landgrave that if he was determined, he should marry secretly and keep quiet about the matter.[199] As a result, on 4 March 1540, Philip married a second wife, Margarethe von der Saale, with