[T]he word “apostle” is Greek for “sent one.” To this we can add the words of St. Paul, who says that preachers must be “sent.” (Rom. 10:15)
Now, what does “to be sent” mean, except that someone in authority over you has conferred the privilege and authority upon you? In fact, it goes without saying that the one who confers the authority must be superior in authority to the one being commissioned, since no one can confer that which he does not possess himself.
In other words, a congregation’s vote cannot suffice, Scripturally speaking, to appoint a man as “pastor,” since the congregation (of inferior authority) cannot confer superior authority upon a man.
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[T]he Gospel message and the necessary authority that accompanies its preaching was passed on from God to Jesus Christ, then to the Apostles. The question we must ask now is this: after the original 12 Apostles, how is this Gospel and apostolic authority passed on? Is it passed on at all? After the death of the last Apostle, can any individual who feels “called” by God simply take up the mission and message and carry on where the Apostles left off?
The answer to this question is plainly “no,” as we have already begun to see from Scripture. The mission and the message can only be passed on by someone who first possessed it. That is, the mission does not merely entail preaching the message, but with it comes the authority to spiritually “reproduce” and pass on the necessary authority to the next generation.