"Has it not become clear to them"—Al-Hasan said, meaning: We clarify for them; [the verse] is read with a 'nun' (i.e., 'nuhdi' instead of 'yahdi'), "how many generations We destroyed before them." He warns and threatens them with the punishment if they do not believe, "they walk in their dwellings," meaning this nation walks in the dwellings of those who passed before them. "Indeed, in that are signs for those of intellect," (al-nuha), who are the believers.