Many classical commentators on the Quran considered that this should be taken metaphorically, as in the sense that God illuminates the world with understanding, rather than literally. The Andalusian scholar Abu Bakr ibn al-Arabi categorized nūr into different levels of understanding from the most profound to the most mundane. Shias believe nūr, in the sense of inner esoteric understanding, is inherited through the Imams, who in turn communicate it to the people.