he should not say, “Be quiet and shut your mouth.”

Maharal (Baer HaGolah #6) One should not reject something which is against one’s views… especially if it is not presented as an attack on religion but is simply an honest expression of the other person’s understanding of faith. Even if it is against one’s religious faith, he should not say, “Be quiet and shut your mouth.” Because if one silences questions there will not be a clarification of that person’s religious understanding. In fact, such a person should be encouraged to speak and fully express how he feels. If sincere questions are silenced that is indicative that the religion is weak and needs to be protected from inquiry. This attitude is the opposite of what some people think. They mistakenly think that silencing questions strengthens religious faith. In fact, however, suppressing of dissent and questions indicates a weak religion. Thus, we find with our ancestors that even if they found something in books against religion they would not simply reject it. (In Daniel Eidensohn, Dass Torah)