The term ministry (Predigtamt, ministerium) is used both by Scripture and the Church in a wider and a narrower sense. In its general sense the word denotes every manner of proclaiming the Gospel or of administering the means of grace, no matter whether this is done by Christians in general, to whom the means of grace have been divinely entrusted, or by called and ordained ministers of the Word (ministri ecclesiae) in the name of the Christian congregation (Pfarramt).
Accordingly we speak of the Christian ministry in the abstract (in abstracto), that is, distinct from the persons who administer it, and in the concrete (in concreto), or as it is vested in called and ordained pastors, who perform its duties in the name of the local congregations. In this special, or narrow, sense we employ the term ministry in this discussion (Pfarramt; Predigtamt im engeren Sinn).
The Christian ministry in its narrow sense (in concreto) presupposes the existence of local churches, for it certainly can be established only where such congregations exist. In this sense the Smalcald Articles (Of the Power and Primacy of the Pope, § 671 aptly say: "Wherever the Church is, there is the authority command to administer the Gospel. Therefore it is necessary for the Church German: die Kirchen to retain the authority to call, elect, and ordain ministers. . . . Wherever there is a true church, the right to elect and ordain ministers necessarily exists."
The Smalcald Articles2 voice the clear doctrine of Holy Scripture on this point. When St. Paul had founded Christian churches on the island of Crete, he commanded Titus (Titus 1, 5) to ordain elders, whom in v. 7 he calls bishops (ἐπισκόπους), in every city (κατὰ πόλιν), that is, in every city where there were local churches. Again, after St. Paul and Barnabas had established local churches in Asia Minor on their first missionary journey, they, on their return trip, "ordained them elders (πρεσβυτέρους) in every church (κατ' ἐκκλησίαν), commending them to the Lord, on whom they believed," Acts 14, 23. Elders so ordained were expressly commanded to "take care of the church of God," 1 Tim. 3, 5; to "take heed to all the flock over the which the Holy Ghost hath made them overseers," Acts 20, 28; to "feed the Church of God," v. 28 b; to "watch ... and warn every one night and day," v. 31; to be "ensamples to the flock," 1 Pet. 5, 3; etc. In short, they were to serve as divinely appointed pastors in their congregations.
Hence we rightly say that the office of the Christian ministry (das christliche Pfarramt) is of divine appointment or command. So also the Apology says Art. XIII, 11 : "The ministry of the Word3 has God's command and glorious promises." Gerhard writes: "The ministry of the Church is a sacred and public office by divine appointment." XIII, 224. And Hutter: "The ministry of the Church has been established ... by God Himself." Cp. Doctr. Theol., p. 606 ff. & Loc. Th., 186.4.
The Christian ministry is called "public," not in view of the place, where its functions are performed, but rather in view of the fact that its functions are executed in the name and by the authority of the congregation, so that even such functions of the ministerial office as are done in private (private Communion; private admonition; private absolution) belong to the public ministry (cp. public service; public servants, etc.). So, then, the divine rule obtains: Wherever true believers are found at one place, they must organize and maintain local churches. And wherever there are local churches, they must also by God's will call official pastors or ministers, who in the name of the congregation preach the Gospel and administer the Sacraments, or who in the name of the congregation execute the Office of the Keys. (Cp. Luther, St. L., III, 723.)