Showing Jesus is the Christ

Acts 18:27-28   
27 And when he desired to cross to Achaia, the brethren wrote, exhorting the disciples to receive him; and when he arrived, he greatly helped those who had believed through grace; 28 for he vigorously refuted the Jews publicly, showing from the Scriptures that Jesus is the Christ.

Paul was encouraged by his fellow believers who were asked to welcome him in Achaia.  There he helped those fellow partakers of God's grace who were encouraged to help him.  He also showed the Jews from scripture who Jesus was, the Messiah who is God's Son.  Paul continued to be faithful to his call in all circumstances.