These stupid AS smears posted by Catholics ignore the same or worse behavior by their saints; what can be inferred from this? That AS is terribly grave, unless you are the Pope doing the expulsion or the Catholic tailor making the prescribed badge that all the Jews were required to wear. That is the history, Luther talked as an AS but the Catholic church DID as an AS. None of Luther's AS rants survived as doctrine nor drove a Jew from his home. The Catholic church would have done well to be an AS like Luther. Instead, the Catholic church participated and drove these events until the outbreak of WWII.
Based on the state of Catholicism, he easily could have learned in the pews while growing up. But he admits it came from the fact that the Jews didn't respond to the Gospel.