The five major fields—God’s signs and attributes, historical dealings with communities, death and the afterlife, rulings, and argumentation—provide a framework for recognizing exceptional passages. Their distinctive features are not identical: one passage gathers divine attributes, another relates an unusually instructive episode, and another precisely defines a legal quantity.
Rhetoric and expression form an additional dimension: some verses stand out because of literary form rather than because they belong to a rare topic. Therefore these passages cannot be reduced to unfamiliar stories or technical words.
Two questions remain distinct: what principal subject does the passage teach, and what is especially striking about the way it treats that subject?