An Explanation of Luther's Small Catechism · Martin Luther
III. HIS WORKMANSHIP.
THE MARKS OF THE CHURCH. The Church is found wherever the Gospel is rightly taught and the Sacraments are rightly administered. For wherever God's Word is preached, some persons believe it, [Isa. 55:10, 11] and where believers are, there is the Church. THE CHURCH IS ONE. It consists of the true believers out of all the different churches, denominations, and sects. There is one Flock, with one Shepherd. [John 10:16] The Church is the Body of which Christ is the Head. [Col. 1:18, Eph 1:22, 23] ITS NAMES. The Church is called _Holy_, because the Holy Spirit works in it and through it, and because its members, though not perfect, lead holy lives. It is called _Christian_, because it consists of those who believe in Christ. It is called _Catholic_ or Universal, because it is meant to include all men everywhere. Catholic does not mean _Roman_ Catholic. MILITANT AND TRIUMPHANT. The Church, consisting of true believers, is one and the same Church on earth and in heaven. On earth it is the Church Militant, because its members are still fighting the good fight of faith. [I Tim. 6:12+] In heaven it is the Church Triumphant, because its members have won the victory of faith. [Rev. 7:9-14, Rev. 2:18, Rev. 3:21] The only way into the Church Triumphant is through the Church Militant.
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