If you spend enough time with Zen or Dzogchen teachers, it is certain that they will at some point roast your sacred cows—whatever they are. They will contradict something you think every good person must believe. (That might be strongly-held political, religious, or cultural values.) Or they may do something you think no holy person ever should. (It might be a politically-incorrect joke, or eating meat, or ranting about how much they hate a kind of music you like.) They may violate fundamental assumptions you did not even know you had.