As for inquiring about the crescent moon—its phases, its waxing and waning—there is no benefit in that for them. The useful question would have been about what they actually need: the practical advantages of the new moons. Therefore Allah said, “Say: They are time-keepers for the people,” thereby clarifying their utility: Allah has made them markers by which people determine acts of worship, business dealings, fixed terms, and the like.

Thus He guided them to the benefits of the new moons and did not answer their question concerning the moon’s physical reality, for that held no advantage for them. Instead, He steered them toward the matters they ought to ask about—the true gateways to knowledge—not toward its surface displays or the superfluous issues they do not require, and even if they do, their need for such matters is minimal.