Because Christians believe that God’s revelation to humankind culminated with and through Jesus Christ, they have had difficulties from the outset recognising Islam as a religion of revelation in its own right, and Muhammad as God’s Prophet and messenger. As a result, down through the history of Christianity, there have been numerous mistaken views about Islam, views that have placed a heavy strain on prospects for a positive relationship between the religions – or have even made such a relationship impossible. Time and again, the Christian side has lacked the necessary respect for the otherness of the other religion, which is also why some of the statements Christians have made about Islam have been grossly disparaging and intentionally polemical. In retrospect, it must be observed that, in dealing with Islam in this fashion, Christians have betrayed the essence of their own religion – which is the heralding of God as love, and the thought and action based on this – and have saddled themselves with guilt as a result. The elements of the Christian image of Islam assembled in what follows are thus to be viewed as historical misunderstandings for which Christians themselves are to blame, and that must be overcome in current dialogue: For centuries, Christians saw Islam as a heresy within Christianity, depicted Muhammad as a false prophet and questioned the credibility of the message he put forward, either by disqualifying Muhammad on moral grounds (e.g. as a womanizer or violator of pacts) or by pronouncing him ill (e.g. an epileptic). Even the first major theological combatant against Islam, St. John of Damascus (d. before 753 CE), a Melkite Christian occasionally in the service of the caliph, characterised Mamád – as he referred to Muhammad – as a false prophet who – he wrote – was passingly familiar with the Old and New Testaments, that he was in contact with the Arian monk Bahira, and that he then created his own heresy and spread a rumour of having received a book sent down to him from heaven. This laid out the main accusations against Islam for the centuries to come. During the Latin Middle Ages, these claims were embellished upon at times in grotesque fashion, e.g. when it was said in Europe that Muhammad had once been a cardinal in the Roman Church, but then, after not being chosen pope, had established a church of his own in his home country of Arabia. Even more abstruse was the notion that Muhammad was the god of the Muslims or one god among many in the pantheon worshiped by Muslims. Parallel to all these excesses, a recurrent effort was also under way to familiarise people with the Qur’an. The study of Arabic was promoted, and a fertile period of translation began. There were studies of Islamic philosophers and theologians (particularly Ibn Sina [Avicenna; d. 1037 CE], al-Ghazali [Algazel; d. 1111 CE] and Ibn Rushd [Averroes; d. 1198 CE]) and explorations of the Qur’an (e.g. Petrus Venerabilis [d. 1156 CE], Thomas Aquinas [d. 1274 CE], Nicolaus Cusanus [d. 1464 CE]) in order to bring discrepancies or heretical misinterpretations to light. During the Enlightenment, Muhammad and Islam often served as defamiliarised attacks upon Christianity: in a negative sense in Voltaire’s (d. 1778 CE) play Mahomet as an example of religious fanaticism, and in a positive sense in Gotthold Ephraim Lessing’s (d. 1781 CE) play Nathan der Weise, in which the Islamic caliph Saladin is presented as a role model of tolerance in questions of religion. Beginning in the early 20th century, and at the direction of the Popes, Catholic theology began taking a positive approach to Islam, primarily on behalf of missionary interests and in search of possible points of departure for the Christian mission among Muslims. A complete reorientation in the relationship with other religions came during the 1960s, both within Protestantism and in the Catholic Church, through the turn towards dialogue with other religions. This marked the first time that Islam was officially perceived as a religion in its own right, and no longer as a mere Christian heresy. The implications of this for Christian theology were laid down in binding form for the Roman Catholic Church by the Second Vatican Council (1962–1965). There are important proclamations on the subject within Protestantism as well, all necessitating a theological elaboration of the concept of interreligious dialogue, its tasks and aims; Christian theologians are currently working on these matters. Where the contemporary view of Islam in Europe is concerned, one factor that must be taken into account is that most of the positions laid out in public discussion do not stem from the Christian churches but are instead a manifestation of a secular view of religion and of the questions to which this view gives rise.