“As for those who disbelieve, their deeds are like a mirage in a desert, which a thirsty man supposes to be water, until, when he comes to it, he finds it to be nothing; but he finds Allah before him, and He pays him in full his due. And Allah is swift in reckoning. (39) Or like layers of darkness in a deep sea, covered by a wave, above which is another wave, above which are clouds—layers of darkness, one above another. When he puts out his hand, he can hardly see it. And whoever Allah does not grant light has no light. (40)”
“As for those who disbelieve, their deeds are like a mirage in a desert”: A mirage is the radiance seen at midday, when the heat is intense, in open wildernesses. It resembles water flowing across the ground, so that whoever sees it thinks it is water; but when he draws near to it, it vanishes and he sees nothing. The āl is that which rises from the ground: a radiance seen between heaven and earth in the morning, like a sheet, in which figures appear elevated; the small appears large, and the short appears tall. The raqrāq occurs in the evenings, and is the shimmering of the mirage—that is, it comes and goes.
“The desert” is the plural of qā‘, meaning a broad, level expanse of land, where mirages occur. “Which a thirsty man supposes to be water”: that is, the thirsty person imagines it to be so. “Until, when he comes to it”: that is, when he comes to what he had seen as water. It was also said: when he comes to the place of the mirage. “He finds it to be nothing”: that is, not as he had estimated and supposed it to be. Likewise, the disbeliever supposes that his deeds will benefit him; but when the Angel of Death comes to him and he is in need of his deeds, he finds that his deeds do not avail him at all or benefit him.
“But he finds Allah before him”: that is, at his deeds; in other words, he finds Allah lying in wait. It was also said: he comes before Allah. “And He pays him in full his due”: that is, the recompense for his deeds. “And Allah is swift in reckoning.”
“Or like layers of darkness”: This is another parable that Allah sets forth for the deeds of the disbelievers. He says: the likeness of their deeds, in their corruption and the ignorance involved in them, is like layers of darkness. “In a deep sea”: that is, a sea deep and abundant in water; the depth of the sea is its greater part. “Covered by”: that is, overlaid by, “a wave, above which is another wave”: waves piled one upon another. “Above which are clouds.” ⦗42/a⦘ Ibn Kathir, in the transmission of al-Qawwās, recited “clouds” with the nominative ending and tanwīn, while “layers of darkness” was read in the genitive as an appositive to “or like layers of darkness.” Abu al-Hasan al-Burrī narrated from him the reading “clouds of darkness,” in a possessive construction. The other reciters read “clouds; layers of darkness,” with both words in the nominative and with tanwīn. According to this reading, the statement ends at “clouds,” after which a new statement begins: “Layers of darkness, one above another”: the darkness of the clouds, the darkness of the waves, and the darkness of the sea, one above another—that is, the darkness of the wave over the darkness of the sea, the darkness of the upper wave over the lower wave, and the darkness of the clouds over the darkness of the wave.
By these layers of darkness He meant the deeds of the disbeliever; by the deep sea, his heart; by the waves, the ignorance, doubt, and bewilderment that cover his heart; and by the clouds, the sealing and stamping of his heart.