In Leviticus 18:3, in Acharei Mot, it is written, "You shall not copy the practices of the land of Egypt where you dwelt, or of the land of Canaan to which I am taking you."
You shall each revere your mother and your father, and keep My sabbaths: I the Eternal am your God. (Leviticus 19:3)
In the first part of this week's parashah, Acharei Mot/K'doshim, the Torah's fullest description of Yom Kippur appears. (Leviticus 16:2-34) But Holy Days, holidays, and festivals develop and evolve as human life changes.
Acharei Mot, the first of this week's two parashiyot, begins on an unsettling note—a reminder of the death of Aaron's sons and the suggestion that such tragedies might occur again unless the priests take specified steps to prevent them
In this week's double parashah, Acharei Mot/K'doshim, there's a one-sentence reference to the mortal sin of Aaron's sons, Nadab and Abihu, who brought "alien fire" into the Mishkan, which we read about in Parashat Sh'mini two weeks ago (see Leviticus 10:1-7).