Surah 74. Al-Muddaththir, Ayah 30

Whereas most of the classical commentators are of the opinion that the "nineteen" are the angels that act as keepers or guardians of hell, Razi advances the view that we may have here a reference to the physical, intellectual and emotional powers within man himself: powers which raise man potentially far above any other creature, but which, if used wrongly, bring about a deterioration of his whole personality and, hence, intense suffering in the life to come. According to Razi, the philosophers (arbab al-hikmah) identify these powers or faculties with, firstly, the seven organic functions of the animal - and therefore also human-body (gravitation, cohesion, repulsion of noxious foreign matter, absorption of beneficent external matter, assimilation of nutrients, growth, and reproduction); secondly, the five "external" or physical senses (sight, hearing, touch, smell and taste); thirdly, the five "internal" or intellectual senses, defined by Ibn Sina - on whom Razi apparently relies - as (1)perception of isolated sence-images, (2)conscious apperceptions of ideas, (3)memory of sense-images, (4)memory of conscious apperceptions; and, lastly, the emotions of desire or aversion (resp. fear or anger), which have their roots in both the "external" and "internal" sense-categories - thus bringing the total of the powers and faculties which preside over man's spiritual fate to nineteen. In their aggregate, it is these powers that confer upon man the ability to think conceptually, and place him, in this respect, even above the angels (cf. 2:30 ff. and the corresponding notes; see also the following note).

The figure nineteen refers to angels appointed to guard Hell. See verse 31 below and the corresponding note.