How did Paul force Jewish believers to blaspheme before his conversion?

Les explains that Paul, then Saul, received authority from the chief priests and voted against believers to have them put to death. He punished them often in every synagogue and compelled them to blaspheme, forcing these Jewish believers—by threat of torture or whatever—to renounce their faith in Jesus. Les notes that religious fanatics are torturous and inhuman, caring little what happens to victims as long as their religion comes out on top. Paul was exceedingly mad against them, persecuting them to strange cities, and went to Damascus to drag them bound back to Jerusalem for trial before the Sanhedrin, Pharisees, and chief rulers, where he could say, put them to death.