Fathers of the Church sang Mary’s praises; especially St Ambrose of Milan (4th century), considered a father of Marian theology, who said of Mary: "She is the Temple of God and not the God of the Temple", and St John of Damascus, regarded as the greatest advocate of Marian devotion in the Eastern Church (7th – 8th century).
Soon after the death of Jesus, Fathers of the Church...
Mary is referred to by the saints very early on.
In the Eastern Church, from 350 onwards, Mary is frequently given the title of “Mother of God”. Moreover, the Virgin Mary is referred to as Mother of the Word Incarnate, both in the "Symbol of the Apostles" and in the "Nicene - Constantinopolitan Creed", the two great affirmations of the Christian faith, used throughout Christendom. As St Gregory of Nazianzus (330-390) writes, Mary has become a model for Christian living: "Christ was born of a Virgin. Women: cultivate your virginity and you shall become the Mother of Christ."
In the early centuries after Christ, the Eastern and Western Churches developed the same Marian theology
In the West, the movement was slower, but the same views were adopted: in the 4th century, Saint Ambrose, Archbishop of Milan, put Mary forward as a model of all the virtues. His influence on the popular understanding of Mary’s spirituality is profound. However, there were difficulties and questions stirring over the virginity of Jesus’ mother. Referring to the doubts and a lack of Faith by some who called Mary’s saintliness into question, "the birth of Christ is a real event, of the flesh but nonetheless miraculous. Through his Incarnation, God does not do away with the flesh, but transcends it." Gradually, the questioning died down, giving way to an absolute recognition of Mary’s saintliness.
Two of the questions asked remained until the 19th and 20th centuries, those of the Immaculate Conception and the Assumption. Because of the Pelagian heresy denying the concept of original sin - and in so doing denying that it was impossible for any being to save himself without the intervention of divine grace – a heresy contended by St Augustine, the West distrusted for centuries the notion of the Immaculate Conception, which, if not properly understood, could lead to the acceptance of this heresy. Nevertheless, beyond the theological discussion, Marian devotion developed irresistibly. Prayers to her proliferated, and feast-days dedicated to her grew in number.
From the time of the Council of Ephesus in the 5th century, Mary is regarded as the Mother of God
In the 5th century came the first arguments. After a more or less quieter interlude, a controversy arose in 428. Anastasius, a presbyter in the church at Constantinople, declared that Mary could not be called Theotokos (Mother of God), but only Mother of Jesus: "can a simple creature give birth to God himself?" ... God’s people hold the veneration of Mary so dear to their hearts that turmoil in the Church, riots and street brawls occur. Anastasius is regarded as sacrilegious, and the Nestorian heresy is proclaimed. Rome is worried. Cyril of Alexandria intervenes robustly to break the heresy. A Council is called at Ephesus in 431 where the role of the Mother of God is fully recognized. August 15th, the feast of Mary Theotokos, is established from this 5th century beginning and icons of Mary grow in abundance.
St Leo the Great (440-461) is the greatest Western Theologian on the subject of Mary. In the 8th century, devotion to Mary reaches new heights with St German of Constantinople (died 733): "God obeys Mary as if she were his Mother, no-one can be saved without Mary, no grace is granted except through her." In the West, the Assumption becomes the most important of the Virgin’s feast-days. (It has already held this position in Greek Church tradition for a long time.) St John of Damascus (died 799) is more moderate, making a distinction between the adoration due to God and the veneration of Mary.
In the 7th century, Marian theology gains structure
Gradually, veneration of the Virgin became more structured. References to the Virgin are found in 8th century sermons in Gaul. In actual fact, between the 7th and 8th centuries, the essential elements of Mary’s spirituality are clarified, both in the Western and Eastern churches; veneration of Mary today rests on these fundamental principles. The theological truths relating to the Virgin Mary that were highlighted by the great Ecumenical Councils may be summarised as follows:
The term “Virgin” when applied to Mary was already used in the most ancient reference texts of the Tradition
On the subject of this dogma, John Paul II commented: "The term "Virgin", when applied to Mary, is already used in the most ancient reference texts of the Tradition: We find it in the second Symbol of Faith of St Epiphanus, in 374. In connection with the Incarnation: the Son of God "was incarnate, that is, he was generated in a perfect way by Mary, the ever blessed virgin through the Holy Spirit" (Ancoratus, 119,5; DS 44). The expression "ever virgin" was taken up by the Second Council of Constantinople (553), which affirms: the Word of God, "incarnate of the holy and glorious Mother of God and ever Virgin Mary, was born of her" (DS 422). This doctrine is confirmed by two other Ecumenical Councils, the Fourth Lateran Council (1215) (DS 801) and the Second Council of Lyons (1274) (DS 852), and by the text of the definition of the dogma of the Assumption (1950) (DS 3903) in which Mary's perpetual virginity is adopted as one of the reasons why she was taken up in body and soul to heavenly glory." (General Audience, August 28th 1996).
As for the dogmas of the Immaculate Conception and the Assumption, these were proclaimed by Popes (1) and not by ecumenical councils. Even if no new dogma was proclaimed, we should also remember that the Second Vatican Ecumenical Council has, in Chapter VIII of the Dogmatic Constitution on the Church "Lumen Gentium", reaffirmed the divine motherhood of the Virgin Mary as well as her position as Mother of the Church and her universal motherhood.
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(1) Read: Reference Texts of the Catholic Church