Of all the things that our Lord prayed for in His High Priestly Prayer on the eve of His Crucifixion, we are struck by His focus on Christian unity (see Jn 17: 11, 21, 22, 23). The unity that our Lord prayed for was not some abstract kind of unity that doesn’t really exist objectively e.g. the kind that claims that we are all part of the one Body of Christ as long as we believe in Him. No, the unity that Jesus speaks about is a very real and very objective reality – in fact, it is the same unity that the Lord Jesus Christ has with His Heavenly Father (v21).
In his epistle to the Ephesians, St. Paul speaks of the unity of the Church in the same way. In Eph 4:4-6, he tells us that the Church’s unity springs from the unity of the Holy Trinity (i.e. there is one Spirit, one Lord, one Father). But what does this unity look like? Is the unity of the Trinity such that there is division, or a differing of minds and wills? On the contrary, St. Paul says clearly that there is one body, one hope, one faith, one baptism.
In other words, true Christian unity is doctrinal unity. It is not a unity that we are called to create; because it is already there by the power of the Holy Spirit. Rather, it is a unity that we must strive to protect. As Catholics, let us never doubt our Lord – let Him be true and every man a liar. Jesus promised us that He would build His Church, and that the gates of Hell would never prevail against her (Matt 16:18). This Church, founded upon the rock of St. Peter, has remained one through the centuries because Christ prayed for it.
As Catholics, may we never be ashamed of clinging to the promises of our Lord - He will continue to build His Church, He has never left her and never will, and she will always remain one. May we remain faithful to our Lord by remaining faithful to His Church. She is our Mother. She is the Body of Christ. She is the Catholic Church.