Acts 9:20-22 Saul Preached Jesus As The Christ, The Son Of God.
From His names and title ‘Son of God’ we can get a glimpse of the message which Paul was now preaching (v. 20). Jesus, the One who saves His people from their sins (Mt. 1:21), is also the Christ or Messiah, the Anointed by the Father (Cf. Acts 18:28). He is also the Son of God, meaning that He was also God (Lk. 22:70-71). The people of Damascus were thus amazed, because it was for this very testimony that Saul had originally begun his journey to the city in order to take any who followed this ‘Way’ back with him to Jerusalem for prosecution (v. 21). At this point Saul is focused on His own people, first to prosecute the members of this community who had accepted Jesus as the Christ, the son of God, and then later to seek to persuade his fellow members of this very same message.
However, despite the opposition, “Saul increased all the more in strength, and confounded the Jews who dwelt in Damascus, proving that this Jesus is the Christ” (v. 22). Saul’s audience at this point were made up of those who had some familiarity with the Hebrew scriptures, therefore the proof for them was his exegesis and exposition of the unified testimony concerning the Messiah as being fulfilled in the man Jesus, who was also the Son of God. No doubt what confounded them was the same thing which confounded the disciples that Jesus taught on the way to Damascus-that He had to fulfill everything in all the scriptures concerning the anointed One, including that He must suffer and die and rise again and return to His glory (Cf. Lk. 24:25-27).