We like to relate with people who seem sincere. We like to do business with people we think we can trust. But, sadly, people are not always the same as they appear. The false teachers who had invaded the Galatian churches did not look or sound bad. They seemed very confident and sincere. The believers thought that they were personally interested in them, and had their good at heart. Certainly they were sincerely confident; but they were sincerely wrong - and the believers were being led away from Christ.
 
Paul was passionate about their spiritual welfare, even though the churches had rejected him and his gospel. The inner pain of their spiritual defection was, to Paul, as personal and inescapable as labour pains. He knew that they would be safe if they were trusting only in Christ, and not on legalistic religious observance. They needed to desire Christ and allow Him to dwell in them so that they became like Him.
 
It is easy to be a religious enthusiast: just be totally convinced about a new idea you have had, be sincere and passionate, and sell your ‘product’ to people who will ‘buy in’. Many people have done that and some have made a lot of money. But the Apostle Paul was different. The gospel was not his idea (Galatians 1:11-12). He did not make any money out of gospel preaching (he chose to pay for his living expenses out of his earnings as a tent-maker). He did not manipulate people and was not a very impressive speaker. But God used him to communicate the truth about Jesus. Like Paul, when you are passionate about what is right and true, God will use you. Otherwise it is like selling fake goods.