6.3 The church of Jesus Christ–a mystery
Everything that church is and will ever be is founded upon the word, work, and nature of Jesus. Jesus Christ is true God and true Man, and thus exhibits two natures (see 3.4.3). This mystery remains unfathomable. Likewise, the nature of the church of Christ is unfathomable: it is also a mystery, it also has a dual nature, and it can likewise only be grasped in faith.
Through Jesus Christ, the Mediator between God and mankind, human beings can obtain salvation. These glad tidings are to be preached and passed on by Apostles (1 Timothy 2: 5-7). In the words of the sermon, the word of Christ is brought to expression in various ways through the activity of the Holy Spirit. It is by hearing this word that faith comes into being (Romans 10: 16-17). In this capacity, the church shares in Christ's ministry of mediation through the proclamation of the gospel.
In its nature, the church of Christ reflects the dual nature of Jesus Christ. His divine nature is concealed or invisible, whereas His human nature is visible or manifest. In His human nature, Jesus aged just as every other human being. He felt pain and fear, and He knew hunger and thirst. Hence He shared in the fate of all humanity, albeit without being subject to sin.
Likewise, the church of Christ has a concealed–or invisible–and a visible–or manifest–side. These two sides of the church of Christ can no more be separated than the two natures of Jesus Christ. Although they are different from one another, they belong together indivisibly.
Like the divine nature of Jesus Christ, the concealed side of the church is ultimately indescribable. Its presence, however, can be perceived in the salvific effects of the sacraments and in the word of God. In the concealed side of the church–which is comprised of those who are properly baptised, who genuinely believe, and who profess the Lord–the four identifying features of church (unity, holiness, universality, and apostolicity) are present in perfect fashion. This side of the church is addressed in the Third Article of the New Apostolic Creed.
The revealed side of the church of Christ, like the Man Jesus, shares in the general history of mankind. In contrast to Him, however, the human beings at work within the church are subject to sin. Hence the errors, aberrations, and lapses inherent in mankind are also to be found in the church. However, the deficiencies of the visible church can neither damage nor destroy the invisible and perfect church, namely the church to which the true believers and elect (see 4.5) belong.
This interconnection and simultaneous distinction between the visible and invisible church can only be grasped in faith. The visible form of the church–the church of Christ in its historical manifestation–is not the object of faith. Rather it is the institution in which, at present, salvation and the nearness of God can be experienced.