Christ is the bond of unity
From a commentary on the gospel of John by Saint Cyril of Alexandria, bishop (c.376-444)
Christ is the bond of unity
All who receive the sacred flesh of Christ are united with him as members of his body. This is the teaching of Saint Paul when he speaks of the mystery of our religion that was hidden from former generations, but has now been revealed to the holy apostles and prophets by the Spirit; namely, that the Gentiles are joint-heirs with the Jews, that they are members of the same body, and that they have a share in the promise made by God in Christ Jesus.
If, in Christ, all of us, both ourselves and he who is within us by his own flesh, are members of the same body, is it not clear that we are one, both with one another and with Christ? He is the bond that unites us, because he is at once both God and man.
With regard to our unity in the Spirit, we may say, following the same line of thought, that all of us who have received one and the same Spirit, the Holy Spirit, are united intimately, both with one another and with God. Taken separately, we are many, and Christ sends the Spirit, who is both the Father’s Spirit and his own, to dwell in each of us. Yet that Spirit, being one and indivisible, gathers together those who are distinct from each other as individuals, and causes them all to be seen as a unity in himself. Just as Christ’s sacred flesh has power to make those in whom it is present into one body, so the one, indivisible Spirit of God, dwelling in all, causes all to become one in spirit.
Therefore, Saint Paul appeals to us to bear with one another charitably, and to spare no effort in securing, by the bonds of peace, the unity that comes from the Spirit. There is but one body and one Spirit, just as there is but one hope held out to us by God’s call. There is one Lord, one faith, one baptism, one God and Father of all, who is above all, and works through all, and is in all. If the one Spirit dwells in us, the one God and Father of all will be in us, and he, through his Son, will gather together into unity with one another and with himself all who share in the Spirit.
There is also another way of showing that we are made one by sharing in the Holy Spirit. If we have given up ourworldly way of life and submitted once for all to the laws of the Spirit, it must surely be obvious to everyone that by repudiating, in a sense, our own life, and taking on the supernatural likeness of the Holy Spirit, who is united to us, our nature is transformed so that we are no longer merely men, but also sons of God, spiritual men, by reason of the share we have received in the divine nature. We are one in mind and holiness, we are one through our communion in the sacred flesh of Christ, and through our sharing in the one Holy Spirit.
Source: The Liturgy of the Hours – Office of Readings
Saint Cyril of Alexandria, bishop (c.376-(444)
St. Cyril of Alexandria was Born at Alexandria, Egypt around the year 376 and was the nephew of the patriarch of Alexandria, Theophilus. He received a classical and theological education at Alexandria and was ordained by his uncle. He accompanied Theophilus to Constantinople in 403 and was present at the Synod of the Oak which deposed John Chrysostom, who was later restored and confirmed as bishop of Constantinople. Cyril succeeded his Uncle as patriarch of Alexandria in 412. Cyril began a series of attacks against the Novatians, whose churches he closed, and against the Jews whom he drove out of the city. In 430 Cyril became embroiled with Nestorius, the patriarch of Constantinople, who was preaching heresies denying Mary as the Mother of God, and opposing the doctrine of the Incarnation. A synod was held in Rome under Pope Celestine I which condemned Nestorius and his teachings. Refusing to recant his positions, Nestorius was excommunicated. In 431 Cyril presided over the third general Council at Ephesus, attended by some two hundred bishops, which condemned all the tenets of Nestorius and his followers. Nestorius was forced into exile.
Cyril wrote treatises that clarified the doctrines of the Trinity and the Incarnation which helped stem the spread of Nestorianism and Pelagianism from taking root in the Christian community. He died in 444 at the age of 68. He was the most brilliant theologian of the Alexandrian tradition. His writings are characterized by accurate thinking, precise exposition, and great reasoning skill. Among his writings are commentaries on John, Luke, and the Pentateuch, treatises on dogmatic theology, an Apologis against Julian the Apostate, and letters and sermons. He was declared a Doctor of the Church by Pope Leo XIII in 1882.