which He promised before through his prophets in the Holy Scriptures, concerning His Son Jesus Christ our Lord, who was born of the seed of David according to the flesh, and declared to be the Son of God with power according to the Spirit of holiness, by the resurrection from the dead. (Romans 1:1-4)
Paul makes a significant affirmation about himself and his mission: called to be an apostle (v. 1). In the early chapters of Acts, the church gathered to elect a new apostle, and it set forth the criteria for apostleship. The first criterion was having been a disciple of Jesus during his earthly ministry; the second was having been an eyewitness of the resurrection; and the third and most important criterion was having been directly and immediately called by Jesus (Acts 1:20-26).
On one occasion Jesus sent out seventy disciples. There were far more disciples than the Twelve. Not all those who were disciples became apostles. We tend to use these words interchangeably, as if twelve disciples and twelve apostles must mean the same thing, but a disciple is simply a learner or a student. Jesus was the Rabbi and enrolled in his school were many disciples. From out of that group he chose twelve to be elevated to the rank of apostle, those who were commissioned to speak for the Master. In the ancient world an apostle was like an ambassador who spoke on behalf of the king. The ambassador’s message carried with it the authority of the one who sent him. The word apostolos in Greek means simple “one who is sent.” “He who hears you hears Me, he who rejects you rejects Me, and who rejects Me rejects Him who sent me” (Luke 10:16).
People often say, “I like to know what Jesus says; it is Paul I do not want to listen to.” Almost all we know about Jesus is that which comes through apostolic authority, so much remarks set Paul against Matthew, or Paul against John. That may not be done with impunity because all of the apostolic writings carry the delegated authority of Jesus himself. That is what it means to be an apostle. That is why the New Testament church is built on the foundation of the apostles.
In the three criteria for apostleship, Paul fails the first two tests: he had not been a disciple of Jesus during Jesus’ tenure on earth, nor had he been an eyewitness of the resurrection of Christ. That is why there were some in the early church who seriously challenged the apostolic authority of Paul. The supreme qualification for apostolic authority was a direct and immediate call by Jesus. I believe that is why, in the book of Acts, the account of Paul’s conversion on the road to Damascus, where Christ called him to be his apostle, is repeated three times. It is to remind the people that Paul is an authentic agent of revelation. He speaks with the authority of Jesus.
The next thing we learn about Paul is that he had been separated to the Gospel of God (v.1). In Latin separated means “segregated,” set apart from the multitude to a specific, sacred, consecrated task. The phrase Paul uses involves a part of speech in the Greek language called the genitive, which indicated possession. He is not saying, “I have been commissioned to announce a message or good news about God.” Rather he is saying that the gospel he has been separted and called to proclaim is God’s gospel. God is the author and owner of it. Paul is simply the messenger whom God has called and set apart to proclaim to people a message that comes from God himself.
If I said, “I have some great news for you,” it would pique your interest. If I added, “This great news comes from God himself,” you may think that I am unhinged, but if you thought for a moment that I was sober in such a statement and that I did have a message from God himself–some good news–you would want to hear it. That is what Paul is saying before he spells out the doctrines of grace. He says, “I have been commissioned to proclaim God’s gospel, the gospel that belong to him. It is his possession, and I am going to communicate it to you.”
-Taken from R.C. Sproul’s The Righteous Shall Life By Faith: ROMANS: St. Andrew’s Expositional Commentary, pgs 17 and 18.