1. The Jews were jealous as Paul was making strong inroads regarding the conversion of Jews, Greeks and pagans to Christianity. As a result the people he converted left the synagogue which in turn lead to a substantial drain on the the Synagogues coffers.
2. Paul is aware that he has to continue preaching the gospel irrespective of what happens. This would be in response to the Lords command to gather the harvest. (Mathew 12: 30)
3. Not at all we have to carry on preaching Gods words under all conditions and to as many people as we can. It is our duty to spread the word of God whenever we have an opportunity.