al-Anbiyāʾ 21:33

Wa huwa'lladhī khalaqa'l-layla wa'n-nahāra wa'sh-shamsa wa'l-qamar, kullun fī falakin yasbaḥūn

"It is He who created the night and the day, the sun and the moon. Each swims in an orbit."

This verse too has been matched in the modern period with celestial mechanics. The boundary I drew at the thirtieth verse holds here as well, and I repeat it: I derive from the verse no shape of orbit, no axis of rotation and no law of motion. What I shall do is give the lexical sense of two words and keep within the classical explanations.

Falak — root ف-ل-ك. The core sense the lexicographers give: roundness, turning.

And the kindred words of the root confirm this picture:

And the last row is worth recording: fulk (ship) is made of the same letters as falak. The lexicographers have drawn a connection between the two: both are things that run along in their own channel. I give this as a note about the root, not as a claim about meaning.

Disagreement is transmitted in the classical commentaries about what a falak is:

I transmit the disagreement and do not impose a preference. And I do not equate the verse with the astronomical conceptions of the classical period, just as I do not equate it with modern models.

The root was analysed in detail at al-Ṣāffāt on 37/143, and precisely this verse was cited there as evidence. The note there:

"The root's original sense: to swim or glide, in water or in air, to flow along. […] Its connection with the sense of swimming: what swims moves off from where it is."

I rely on that treatment. And here the root's original sense is at work: sabḥ — to swim.

The description the lexicographers give is this: sabḥ is to move forward in water or in air, by one's own power, without meeting resistance. That is, the word conveys two things: motion and freedom.

I give this as a note about the word and build no claim of physics upon it.

And the most striking grammatical point of the verse is here.

The verb is yasbaḥūna — with wāw-nūn, that is, the plural used of rational beings (those possessed of intellect). Yet the subjects are the sun, the moon, the night and the day.

The grammarians' explanation: when things without intellect are told as though doing something belonging to those with intellect, they receive the treatment of rational beings. There are several instances of this in the Qurʾān.

And this builds a line with the nineteenth and twentieth verses of the sūra — I record this as my own reading:

The same root, thirteen verses apart, in two different forms and for two different subjects. And in both the plural of rational beings is used. This is a fact that can be verified within the sūra.

كُلٌّ — it carries nunation, and the grammarians count this as having its second term of annexation elided: kulluhum — "each of them". And there is disagreement over whom each covers:

I transmit the disagreement and do not impose a preference. And the block closes here.