Belief in the incarnation of God the Son through Mary is the basis for calling her the Mother of God, which was declared a dogma at the Council of Ephesus in 431. At the Second Vatican Council and in Pope John Paul II's encyclical Redemptoris mater, she is spoken of also as Mother of the Church.
Growth of Roman Catholic veneration of Mary and Mariology has often come not from official declarations, but from Marian writings of the saints, popular devotion, and at times reported Marian apparitions. The Holy See approves only a select few as worthy of belief; most recently the 2008 recognition of apparitions as far back as 1665.
Further pious veneration of the Blessed Virgin Mary encouraged by Popes are exhibited in the canonical coronations granted to popular Marian images venerated in a particular locality all over the world, while Marian movements and societies with millions of members have arisen from belief in events such as Akita, Fátima, and Lourdes, and other reasons.
In Roman Catholic teachings, the veneration of Mary is a natural consequence of Christology: Jesus and Mary are son and mother, redeemer and redeemed. This sentiment was expressed by Pope John Paul II in his encyclical Redemptoris mater: "At the centre of this mystery, in the midst of this wonderment of faith, stands Mary. As the loving Mother of the Redeemer, she was the first to experience it: 'To the wonderment of nature you bore your Creator'!"
In the Roman Catholic tradition Mariology is seen as Christology developed to its full potential. Mary is seen as contributing to a fuller understanding of the life of Jesus. In this view, a Christology without Mary is not based on the total revelation of the Bible. Traces of this parallel interpretation go back to the early days of Christianity and numerous saints have since focused on it.