Shemini - Chamishi
…Or Perhaps Not
Moshe found out that Aharon's surviving sons had burned the goat of the sin offering instead of eating it. He became angry and yelled at them. Aharon intervened.
"You saw what happened today. If we had eaten that offering, would it really have been what G-d wanted?"
Moshe had to admit that Aharon was correct. (In practice, an onen – a person who has lost a close relative before the deceased is buried – may not serve or eat from sacrifices. See Rashi on 10:19, citing Talmud Zevachim 101a. Moshe admitted that he had learned this halacha but forgotten it.)