Gerhard, “On the Ministry”

From Gerhard, "On the Ministry," part 1 (forthcoming, 2011), § 61:
(VI) The apostles at first were called by Christ Himself immediately; later He instructed them in His own school, and then sent them out into all the world to preach the Gospel. Matt. 10:1: “Having called to Himself His twelve disciples, He gave them power over unclean spirits.” Verses 5–7: “Jesus sent out these twelve, saying to them: ‘Go and preach,’ ” etc. John 20:21: “As the Father has sent Me, even so send I you.” Matt. 28:19 and Mark 16:15: “Go and teach all nations.” As the apostles were about to write to the churches, they diligently and carefully emphasized their calling in the introductions
to their Epistles to prove that God had sent them and that they were to be considered as legitimate ministers of the church. Hence we have: “Paul, a called apostle” (Rom. 1:1; 1 Cor. 1:1; 2 Cor. 1:1; Gal. 1:1; etc.); “Peter, an apostle of Jesus Christ” (1 Pet. 1:1).

(VII) By a solemn call, those who succeeded the apostles in the teaching office were placed in charge of the churches that they governed. Acts 14:23: “When Paul and Barnabas had established presbyters for the people of Antioch in every church, and had prayed with fasting, they committed them to the Lord.” 1 Tim. 4:14: “Do not neglect the grace that is in you, which was given to you by prophecy with the imposition of the hands of the presbytery.” 2 Tim. 1:6: “I admonish you to stir up the gift of God that is in you through the imposition of my hands.” 1 Cor. 4:17: “I sent Timothy to you to remind you of my ways, which are in Christ.” 1 Thess. 3:2: “We sent Timothy, our brother and God’s minister in the Gospel of Christ, to strengthen you,” etc.

(VIII) The next successors of the apostles in the teaching office again committed the ecclesiastical ministry, with the consent of the church, to certain men who were indeed suitable. No one was allowed to leap into it by his own authority. 1 Tim. 5:22: “Do not lay hands on anyone quickly, nor participate in the sins of others.” 2 Tim. 2:2: “What you have heard from me before many witnesses commit to faithful men who are fit to teach others.” Titus 1:5: “This is why I left you in Crete, that you might establish presbyters in every town.”