The 211th mitzvah is that we are commanded to fear our parents. We should think of them as we do of someone whom people fear, and who is able to administer punishment,1 such as a king; and act towards them as we do with someone we fear can do us harm.
The source of this commandment is G‑d's statement2 (exalted be He), "A person shall fear his mother and his father."
The Sifra3 says, "What constitutes 'fear'? Not to sit in their seat, not to speak instead of them, and not to contradict them."
The details of this mitzvah are also explained in tractate Kiddushin.4
