Systematic Theology, by Louis Berkhof - New Leaven

Church as an institution (also called apparitio and institutio) have their spiritual
background in the invisible Church. However, though it is true that these are two
different aspects of the one visible Church, they do represent important differences. The
Church as an organism is the coetus fidelium, the communion of believers, who are
united in the bond of the Spirit, while the Church as an institution is the mater fidelium,
the mother of believers, a Heilsanstalt, a means of salvation, an agency for the
conversion of sinners and the perfecting of the saints. The Church as an organism exists
charismatic: in it all kinds of gifts and talents become manifest and are utilized in the
work of the Lord. The Church as an institution, on the other hand, exists in an
institutional form and functions through the offices and means which God has
instituted. The two are co-ordinate in a sense, and yet there is also a certain
subordination of the one to the other. The Church as an institution or organization
(mater fidelium) is a means to an end, and this is found in the Church as an organism, the
community of believers (coetus fidelium).
C. VARIOUS DEFINITIONS OF THE CHURCH.
The Church being a many-sided entity has naturally also been defined from more
than one point of view.
1. FROM THE POINT OF VIEW OF ELECTION. According to some theologians the Church
is the community of the elect, the coetus electorum. This definition is apt to be somewhat
misleading, however. It applies only to the Church ideally considered, the Church as it
exists in the idea of God and as it will be completed at the end of the ages, and not to
the Church as a present empirical reality. Election includes all those who belong to the
body of Christ, irrespective of their present actual relation to it. But the elect who are yet
unborn, or who are still strangers to Christ and outside of the pale of the Church, cannot
be said to belong to the Church realiter.
2. FROM THE POINT OF VIEW OF EFFECTUAL CALLING. To escape the objection raised to
the preceding definition, it gradually became customary to define the Church from the
point of view of some subjective spiritual characteristic of those who belong to it,
especially effectual calling or faith, either by naming such a characteristic in addition to
election, or by substituting it for election. Thus the Church was defined as the company
of the elect who are called by the Spirit of God (coetus electorum vocatorum), as the body
of those who are effectually called (coetus vocatorum), or, even more commonly, as the
community of the faithful or believers (coetus fidelium). The first two of these definitions
serve the purpose of designating the Church as to its invisible essence, but give no
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