Between verses 25 & 26 of Acts 9, there is a gap of about three years. Paul did not go immediately to Jerusalem after leaving Damascus, but he went down to the area of Mt. Sinai in Arabia. He was there for three years as the Lord Jesus taught him and helped him to better understand the Scriptures. It was a time of solitude. It was a time of seeking God. It was a time of great spiritual revelation for Paul. God used that time to reveal to the apostle His amazing grace, apart from the Law. For three years Paul was instructed personally by Jesus Christ.