How are we assured that the grace of God abides in the true Church?
The Church is precisely the means by which God, as a loving Father, gives us the highest possible assurance that we are “beloved in Christ” (Rom 1:7; Eph 1:6), “that you may know that you have eternal life” (1Jo 5:13).
Established by Christ himself and declared to be “the pillar and foundation of the truth” (1Ti 3:15; see Q010, Q017), the Church is infallible in this precise sense: in uniting people to Jesus Christ through her administration of the Holy Mysteries, she cannot fail, because it is the Lord and Savior himself who cannot fail to save his people (Mat 1:21; see Q083, Q130).
The Apostle Paul writes that God the Father gave Jesus Christ to be “head over all things for the sake of the Church, which is his body, the fullness of him who fills all in all” (Eph 1:22–23; see Q151, Q259); and to the pastors of the Church he says: “Keep watch over yourselves and over all the flock in which the Holy Spirit has made you overseers: to shepherd the Church of the Lord and of God, which he has purchased with his own blood” (Act 20:28, a text which, in either of its ancient readings, ‘Church of God’ or ‘Church of the Lord,’ bears witness to the divinity of the Crucified; see Q259, Q357). Because the Head of the Church is Jesus Christ, divine and human in a single person, the uncreated Word full of grace and truth, he also fills his Body, the Church, with grace and truth (Joh 1:14, 17; see Q139, Q150).
Admittedly, the individual and localized manifestations of the Church, such as the Churches of Ephesus, Laodicea, or Pergamum in the book of Revelation, may become infected by the presence (and tolerance) of heretical or immoral members and teachers. Yet, in the administration of the divinely established Mysteries, the Church infallibly witnesses to God’s grace toward mankind and unites God’s people to the Body of Christ unto salvation.
