Christian churches teach various doctrines concerning Mary, and she is the subject of much veneration. The area of Christian theology concerning her is known as Mariology. The conception of her son Jesus is believed to have been an act of the Holy Spirit, and to fulfill the prophecy of Isaiah that a virgin would bear a son who would be called Immanuel. The Roman Catholic Church, Eastern Catholic and Eastern Orthodox Churches venerate her as the Ever-Virgin Mother of God (Theotokos), who was specially favoured by God's grace and who, when her earthly life had been completed, was assumed bodily into Heaven. Some Protestants, including certain Anglicans, Methodists and Lutherans, embrace veneration of Mary and also hold some of these doctrines. Others, especially in the Reformed tradition, question or even condemn the devotional and doctrinal position of Mary in the above traditions. Mary also holds a revered position in Islam.