20 Immediately he preached the Christ in the synagogues, that He is the Son of God. 21 Then all who heard were amazed, and said, “Is this not he who destroyed those who called on this name in Jerusalem, and has come here for that purpose, so that he might bring them bound to the chief priests?” 22 But Saul increased all the more in strength, and confounded the Jews who dwelt in Damascus, proving that this Jesus is the Christ.
Chapters 9 and 10 form an introduction to the missionary enterprises that follow in the remainder of the book of Acts. First, we hear of Paul’s conversion and trials of his early Christian life, then we learn of Peter’s call to a broader scope of ministry. These two chapters, therefore, introduce the mighty missionary enterprises of both Paul and Peter.
Paul now made it apparent to all that his faith was genuine. Verses 20-31 set forth the authenticity of Paul’s conversion.
Immediately he [Paul] preached the Christ [Messiah] in the synagogues,
Paul immediately preached his first sermon in Damascus in the synagogues. The content of his message was “Jesus” as the Messiah.
that He is the Son of God.
Note the word “is.” Paul’s message was that He is God’s Son (Ga 1:16). “Son of God” is a reference to His deity (Mt 26:63; Acts 10:36).
Then all who heard were amazed, and said,
Everyone in the synagogues was amazed that the persecutor of Christians now affirmed that Christ is God’s Son.
“Is this not he who destroyed those who called on this name in Jerusalem, and has come here for that purpose, so that he might bring them bound to the chief priests?”
The reaction of those in the synagogues was one of difficulty in resolving the idea that the persecutor of Christians now proclaimed that Jesus was the Savior-Messiah.
But Saul increased all the more in strength,
Paul became more and more empowered to do ministry as the Spirit gave him capacity to become knowledgeable about Christianity. The strength here refers to Paul’s ability to connect Christ with the Old Testament Scriptures, especially Messianic prophecies.
and confounded [baffled] the Jews who dwelt in Damascus,
The Jews could not respond adequately to Paul’s arguments. They were baffled by his arguments from Scripture.
proving that this Jesus is the Christ.
The Greek word “proving” is from the word symbibazw, meaning to join or put together. The idea is that Paul assembled Old Testament passages to prove how Jesus fulfilled them. His skill from his training under Gamaliel clearly demonstrated itself.
We establish the truth of Christianity from Scripture.
As Paul read the Old Testament after his conversion, he began to see where Christ everywhere fulfilled prophecy. Believers establish conviction in their beliefs from the Word of God. We live in a day of experiential Christianity, which builds faith on a fragile foundation. The solid foundation of Christianity is the Word of God.
New believers especially want to share the gospel with their relatives and friends. They cannot wait to tell what happened to them (Acts 4:20; 1 Co 9:16).