 Because you go back prior to Paul's conversion, Paul was a member of the Sanhedrin. He was also a Jewish male. In the Jewish culture, when you go to the Mishnah and you study the Mishnah, which is kind of the code for all the Jews of how they're to live their lives, it all says that at 18 years old, if a Jewish male is not married, he is not an adult. He is not a man.