The lightning almost snatches away their sight. Whenever it gives them light, they walk in it; and when it becomes dark over them, they stand still. And if the One God had willed, He would have taken away their hearing and their sight. Indeed, the One God is powerful over every thing.
This verse continues the storm parable of the previous verse. There, the Qur’an spoke of a heavy downpour, darknesses, thunder, lightning, and thunderbolts; a scene in which the hypocrites put their fingers in their ears out of fear of death. Now verse 20 focuses on the brief moments of illumination and darkness. They do not possess a steady light in relation to guidance. A flash sometimes falls upon their path, they walk a little, and when that brightness disappears, they stand still.
Lightning in this verse should not be read through the modern sense of electricity. In the language of the verse, lightning is the sudden, passing flash of the sky in the middle of a storm; a short light that shows the path for a moment, but does not replace the sun, a steady lamp, or an inner light. The image is that truth sometimes appears before them with such forceful clarity that it almost snatches away their sight. Yet that seeing does not become lasting guidance, because the problem is not only the absence of light; the problem is that direction and true trust have not formed within them.
The phrase “whenever it gives them light, they walk in it” shows that their movement depends on outward conditions. When a sign of victory, safety, benefit, or brightness appears on the path of truth, they also move along. But their companionship is not rooted faith. Mashaw, “they walked,” suggests calm and conditional movement: not a loving rush toward truth, not complete surrender, but stepping forward only as long as the light appears useful to them.
By contrast, “when it becomes dark over them, they stand still” shows that when the outward brightness is cut off, their movement is also cut off. Qamu, in this context, is not merely ordinary standing. It is an image of stopping, helplessness, and being locked in place. When they face hardship, ambiguity, danger, or the loss of benefit, they no longer have the inner force to continue. This is the same unstable, edge-bound faith: it moves with light and stops with darkness.
In the previous verse, ears were highlighted because they were fleeing the thunderbolt and the warning. At the beginning of this verse, sight comes forward because the subject is lightning and illumination. But at the end of the verse, hearing and sight are brought together: if the One God had willed, He would have taken away their hearing and their sight. This shift is very precise. They close their ears so that they do not hear the warning, and they keep their eyes open for useful flashes of brightness. Yet divine power could take away both faculties of reception. Still, the verse does not say that this has been done; it says that if He had willed, He would have done it. So time, testing, and the possibility of return still remain.
The ending places this whole unstable condition within the power of the One God. Their movement and stopping, the brightening and darkening of the path, the lightning almost snatching their sight, and the continued presence of hearing and seeing are none of them outside His power. He is able to take away every faculty of perception, but as long as the signs continue to appear, the human being remains within the field of responsibility.