And let me tell you one thing, my friend. If I were you I would have stayed at home. What you have done will not please the Earth. It is the kind of action for which the goddess wipes out whole families.
-- Obierika (Chapter 8 paragraph 26)

Importance: In a discussion with his friend Okonkwo, Obierkia tells Okonkwo that he should not have taken part in the murder of Ikemefuna because it is for actions like this one that the gods and goddess punish entire families.

In his anger he had forgotten that it was the Week of Peace. His first two wives ran out in great alarm pleading with him that it was the sacred week.
-- Narrator (Chapter 4 paragraph 17)

Importance: Okonkwo is punished for beating his wife during the Week of Peace even though his wife was the one at fault in the incident. It was against the laws of the village to say a cruel word to anyone...