The pastor, an ambassador for Christ
The ambassador is a representative, a spokesman for somebody else. Malta's ambassador in London is chosen and appointed by the Maltese government to represent the nation in a foreign country. In this capacity he is expected to speak the Maltese's government's mind to England. Going beyond this is not only irresponsible but also shows an arrogant spirit. He does not invent the policy; he simply explains what it is. He relays what he himself has received.
Now the office of pastor may be compared to such a role. For an ambassador is a man called to a high position and rank, employed by the nation to represent the dignity and power of the nation. Being on official business he speaks only what his own government orders him to speak, nothing more and nothing less. He might not take pleasure or even agree to some of the things he has to say, but fulfilling his role as ambassador he speaks only what he is commissioned to speak. He reflects the proper and official position and dignity of his leaders who placed him in such an office. He is the mouthpiece of his superiors.
In a similar way the pastor is related to his Master, Christ. He represents him and his kingdom. He is indeed invested with authority and power, but not to use it according to his whim. He has words to say, but not his own; his message is Christ's. He only brings it to the hearing of the people. In a sense the whole church is sent, every saved person is to go out relay the gospel to every creature, but in particular this sacred trust is invested in the pastor, who is peculiarly called to such a task, insomuch that he takes care not to be embroiled in the affairs of this life, but is ambitious to please the One who enlisted him. He is fully conscious that though he is related intimately to the church, he is ultimately to give an account to Christ on that Day. He will receive stricter judgment for he speaks in the official capacity of herald and ambassador.
This word-picture has the backing of Scripture: 2 Corinthians 5:20 - "we are ambassadors for Christ," the term being presbeia, from the same word-family of presbyteros, elder. Thus Paul does not restrict the ambassadorship to the apostolate, but by such an expression extends it implicitly to the eldership. It is indeed an awesome task to speak, not on your own initiative, but to speak the mind of the Christ, even as he gave us the Father's words. "Whatsoever he commands me, that speak I to the world." "The words I speak are not mine but the Father's which sent me."
So the pastor is commissioned by a higher authority. It is the Lord of heaven and earth who places his hand upon him and tells him to go. Indeed he is conscious of his weakness, he is simply an earthen vessel, but this is for the very purpose so that when the ambassador accomplishes something, the power may be known to be from above and not intrinsically his. In this way God is glorified.
Going in the world, he is entrusted with the ministry of reconciliation. More than anything else, and with a sense of urgency, the world needs to hear a clear message how it may be reconciled to God. The pastor makes his appeal, "Be ye reconciled to God," and he shows how, "For he who knew no sin God made him to be sin for us, that we might become the righteousness of God in him." It is reconciliation by substitutionary atonement.
The pastor must be jealous to guard the gospel, the sacred deposit of the faith, and not dilute it, or change it in any shape or form. It must be left intact. With love and compassion he addresses the lost, speaking as it were "the very oracles of God." That is why in his capacity as pastor he must above all things be biblical. Otherwise he would be building with wood, hay and stubble.