What does a war have to do with being a chosen vessel

In Acts 9:15, God said, “But the Lord said to him, 'Go, for he is a chosen vessel of Mine to bear My name before Gentiles, kings, and the children of Israel'.” And this chosen one of God did a great work for the Lord.<br />The Apostle Paul told the people of Galatia, “I marvel that you are turning away so soon from Him who called you in the grace of Christ, to a different gospel, which is not another; but there are some who trouble you and want to pervert the gospel of Christ. But even if we, or an angel from heaven, preach any other gospel to you than what we have preached to you, let him be accursed” (Galatians 1:6-8).