al-Ḥijr 15:21

Wa in min shayʾin illā ʿindanā khazāʾinuhu wa mā nunazziluhu illā bi-qadarin maʿlūm

"There is nothing whose storehouses are not with Us; and We send it down only in a determined measure."

The plural of khizāna. The root خ-ز-ن: to keep a thing hidden, to take it into safekeeping, to store it up. Khāzin — a treasurer, one who keeps.

The picture in the word is worth recording: a store is not what is unused but what is kept; it is held to be brought out at the moment of need.

And the pattern of the sentence is twice a ḥaṣr: wa in min shayʾin illā… and wa mā nunazziluhu illā… — two restrictions in succession, leaving no exception.

I record this as an observation about the word order: the first restriction determines the scope (nothing is excluded), the second the measure (no sending down is without measure).

The ق-د-ر root was analysed in detail at al-Qadr and taken up once more at al-Qamar 54/49 (innā kulla shayʾin khalaqnāhu bi-qadar). I do not repeat it here.

What was recorded in the section on al-Qadr holds here too, and I rely on it:

Qadara — he measured, he shaped, he determined its quantity. Its derivatives: qadar (a determined measure), miqdār, taqdīr, qudra. And the relation between determining and worth is built into the language itself: to know the qadr of a thing is to give it its right measure.

The difference belonging here is this, and it must be recorded:

In al-Qamar the measure is attached to creating, here to giving. And an attribute has been added to the measure here: maʿlūm — known. In al-Qamar this attribute is absent.

I record this as my own reading, and its ground is the presence of the attribute: the measure's being "known" says that there is one who knows it. That is, the verse does not merely state a quantity; it says that the quantity is not random, that it is on record. And this is the same attribute as the kitābun maʿlūm of the fourth verse of the sūra.