Commentary
Allah swears by the objects and phenomena mentioned in verses [ 1-7], which gives these creations an added significance and draws man's attention to them. Man ought to reflect on these phenomena and try to appreciate their value and the purpose of their creation. The first oath is taken by:
وَالشَّمْسِ وَضُحَاهَا (I swear by the sun and his broad light,...91:1). The phrase and his broad light' is, though conjoined to 'by the sun' by means of the conjunctive particle 'and', the context indicates that 'broad light' is in adjectival position qualifying shams 'the sun', that is to say, 'I swear by the sun when it is in the time of forenoon. The word duha is that part of the day when the sun rises [ early in the morning ] and goes up slightly higher [ on the sky ], and its light spreads on the earth. Man observes it to be near to himself and observes it fully on account of lack of heat.