“Unity of government is not less essential to the Church of Christ than unity of doctrine. Our divine Saviour never speaks of His Churches, but of His Church. He does not say : ” Upon this rock I will build my Churches,” but, ” Upon this rock I will build my Church,” from which words we must, conclude, that it never was His intention to establish or to sanction various conflicting denominations, but one corporate body, with all the members united under one visible Head ; for as the Church is a visible body, it must have a visible head.”
Cardinal Gibbons:
Faith of Our Fathers