The Scriptures provide the fundamental material for Orthodox ecclesiology, but the dogmatic and central phrase of the Nicene Creed is also very important, in which the Church is defined as a central mystery of the Christian faith. Orthodoxy refuses to concur with a conception of the Church that has become increasingly common in the West since the Reformation – and that is the tendency to strictly demarcate the heavenly and the earthly church into separate entities. It applies, against this dichotomous understanding, the typological understanding of the Incarnate Lord’s unity with his own body. The Church, as the apostle clearly taught, is the mystical Body of Christ. Orthodox thought has also used the typology of the Holy Trinity in its ecclesiology. The Church is, then, to be understood as the icon of the Holy Trinity also.