Why does the Qur'an call the sun a "blazing lamp" (sirājan wahhājā) in 78:13?

Answer

In 78:13 Allah says "and placed a blazing lamp" (wa-jaʿalnā sirājan wahhājā), which the commentators unanimously identify as the sun. Sirāj means a lamp or lantern—something that gives light by its own burning—and wahhāj intensifies this to "blazing," combining brilliant light with intense heat. Ibn Kathīr explains that wahhāj joins both qualities together: radiant illumination and burning warmth. Al-Qurṭubī likewise notes the sun's combination of light and heat in this single word. The image works on two levels in the passage. First, it is a favour: the sun's light and warmth, together with the rain of the following verse, ripen the grain and gardens that sustain life. Al-Saʿdī notes the sun's heat is part of how God matures the earth's produce. Second, it is a sign pointing to resurrection—the larger argument of Surah An-Naba. It is also worth noting that the Qur'an consistently calls the sun a sirāj (a self-lit lamp) while calling the moon a nūr (reflected light), a consistent distinction in its vocabulary that the commentators recognized—the same word sirāj for the sun appears in 25:61 and 71:16. But notice what the chosen word is. Not "a great fire," not "a vast star"—a lamp. A lamp is something a host lights and hangs for the people in the house. The word quietly carries the relationship: the sun was placed there, for you, on purpose. Step outside tomorrow morning and let the warmth land on your face, and you are feeling the very favour this verse is naming—a lamp hung above you so that your day has light and your food can grow. You did not arrange it; it was set blazing on your behalf before you were born. And that is exactly why the surah moves from this lamp to the question of resurrection: the One with the power to light a sun and hang it steady over the whole earth, morning after morning, is not a God who would find it hard to bring you back.