Thank you for the question on the Church Age, “Would the church age and the time of the gentiles have occurred without the apostle Paul?”
The Church Age is founded on the words of Jesus that his followers are to be his witnesses both in Jerusalem, Judea and Samaria, even to the ends of the world (Acts 1:8) as well as make disciples of those who believe in Jesus as Savior and Lord (Matt. 28:18–20).
The Church Age began on the Day of Pentecost when the Holy Spirit came upon the believers in the Upper Room where the Holy Spirit enable them to declare the Gospel of Salvation to the Jews and to the proselyte Gentiles to the Jewish faith.
Acts 2 says this, “Now there were staying in Jerusalem God-fearing Jews from every nation under heaven. 6 When they heard this sound, a crowd came together in bewilderment, because each one heard their own language being spoken. 7 Utterly amazed, they asked: “Aren’t all these who are speaking Galileans? 8 Then how is it that each of us hears them in our native language? 9 Parthians, Medes and Elamites; residents of Mesopotamia, Judea and Cappadocia, Pontus and Asia,[b] 10 Phrygia and Pamphylia, Egypt and the parts of Libya near Cyrene; visitors from Rome 11 (both Jews and converts to Judaism); Cretans and Arabs—we hear them declaring the wonders of God in our own tongues!” 12 Amazed and perplexed, they asked one another, “What does this mean?” (NIV).
Acts 8 says this, “4 Those who had been scattered preached the word wherever they went. 5 Philip went down to a city in Samaria and proclaimed the Messiah there. 6 When the crowds heard Philip and saw the signs he performed, they all paid close attention to what he said. 7 For with shrieks, impure spirits came out of many, and many who were paralyzed or lame were healed. 8 So there was great joy in that city.
And after that experience, he shared with the Ethiopian Eunuch as well as to those living in Caesarea (Acts 8:26–40). Up to this point, the Gospel was preached within the surrounding borders of Israel. God used the Apostle Paul to begin the spread of the Gospel of Salvation to the nations.
Paul recounts in Galatians that he is the apostle to the Gentiles while the 12 apostles were apostles to the Jews. In Galatians 2, he says this, “ As for those who were held in high esteem—whatever they were makes no difference to me; God does not show favoritism—they added nothing to my message. 7 On the contrary, they recognized that I had been entrusted with the task of preaching the gospel to the uncircumcised,[a] just as Peter had been to the circumcised.[b] 8 For God, who was at work in Peter as an apostle to the circumcised, was also at work in me as an apostle to the Gentiles. 9 James, Cephas[c] and John, those esteemed as pillars, gave me and Barnabas the right hand of fellowship when they recognized the grace given to me. They agreed that we should go to the Gentiles, and they to the circumcised. 10 All they asked was that we should continue to remember the poor, the very thing I had been eager to do all along” (NIV).
In my view, God used the 12 Apostles to begin the Church Age with the message of salvation on the Day of Pentecost. The early followers of Jesus spread the Gospel message of salvation in Israel and to the surrounding countries. Yes, God used the Apostle Paul to spread the Gospel to non-Jews. He was very instrumental in bringing the Gospel to the nations.
SUMMARY: The Church Age has its foundation on the words of Jesus that his followers are be his witnesses and to make disciples of all nations.
For further insight and discussion: