(21) “And thus We caused them to be discovered, so that people might know that Allah’s promise is true and that there is no doubt about the Hour. When they disputed among themselves concerning their affair, they said, ‘Build a structure over them. Their Lord knows best about them.’ Those who prevailed in the matter said, ‘We will surely build a mosque over them.’”
Allah Most High informs us that He made the people aware of the circumstances of the Companions of the Cave. This—and Allah knows best—occurred after they had awakened, sent one of their number to buy them food, and instructed him to conceal himself and their circumstances. Allah willed something that would benefit the people and increase the youths’ reward: the people saw in them one of Allah’s signs with their own eyes, proving that Allah’s promise is true, without doubt, uncertainty, or improbability. They had previously been disputing among themselves about this matter: some affirmed the promise and the recompense, while others denied them. Allah therefore made their story a source of greater insight and certainty for the believers and a proof against those who rejected the truth. The youths also received the reward arising from this event. Allah made their story widely known and elevated their standing until those who discovered them held them in great esteem.
“They said, ‘Build a structure over them. Their Lord knows best about them.’” Those who prevailed in the matter—namely, those who held authority—said:
“‘We will surely build a mosque over them,’” meaning: a place in which we may worship Allah Most High and through which we may remember their circumstances and what befell them.
This practice is prohibited. The Prophet—peace and blessings be upon him—forbade it and condemned those who engage in it. Its mention here does not indicate that it is free from condemnation. The context concerns the high esteem and praise accorded to the Companions of the Cave: matters reached the point that these people said, “Build a mosque over them.” This came after the Companions of the Cave had intensely feared their people and had taken great care lest they be discovered. Yet matters ultimately came to what you now see.