Marks of the Church
The Marks of the Church are those things by which the True Church may be recognized in Protestant theology. Three marks are usually enumerated: the preaching of the Word, the administration of the sacraments, and church discipline. The Belgic Confession devotes a chapter to the "Marks of the True Church" and lists them as follows:
Louis Berkhof notes that Reformed theologians have differed as to the number of marks: Theodore Beza spoke of only one, John Calvin and Heinrich Bullinger spoke of two, while Peter Martyr and Zacharias Ursinus spoke of three – preaching, sacraments and discipline. Nevertheless, Edmund Clowney points out that Calvin "included discipline in the proper observance of the sacraments." Albert Mohler calls church discipline the "missing mark" of the church.