Tafsir of Ya seen 36:40

"It is not for the sun to overtake the moon" (meaning: to be made subservient and easy [to overcome], as in your saying: "It is for the fire to burn the garment," or that it is fitting and appropriate, meaning: wisdom, as in your saying: "It is for the king to honor the scholar." Many have chosen the first meaning. The root of yanbaghī (to befit/possible) is the derivative of baghā, which means to seek; when it is made derivative and precedes the verb, it means that it is made easy and subservient. The negation in reality returns to yanbaghī, as if it were said: "It is not made easy for the sun, nor is it made subservient [to the moon] that it should overtake the moon" (meaning: within its [the moon's] dominion, by gathering with it at the time that Allah the Exalted has delimited and made an arena for its dominion). For He, Majestic and Exalted, has established for the administration of this world, according to wisdom, a specific limit and a fixed time for each of the two luminaries, the sun and the moon, in which its dominion appears. Therefore, neither of them enters into the dominion of the other; rather, they succeed one another until the command of Allah the Exalted comes.

This sentence serves to negate that the sun should overtake the moon within what has been allotted to it. His saying, Exalted is He, "nor does the night precede the day" is to negate that the moon should overtake the sun within what has been allotted to it, meaning: the sign of the night does not precede the sign of the day, nor does its dominion appear while the dominion of the other is appearing. This meaning is alluded to by the words of Qatadah, al-Dahhak, ‘Ikrimah, and Abu Salih. Al-Zamakhshari chose this to correspond with His saying, Exalted is He, "It is not for the sun to overtake the moon," and because the discussion in the two verses is indicated by His saying, Exalted is He, "And the sun runs..." and the two verses at the end, "each in an orbit swimming."

The expression "overtaking" was used first, and "preceding" second, according to what is in al-Kashshaf, to suit the state of the sun in the slowness of its motion and the state of the moon in its speed. It was not said, "nor does the moon precede the sun," so that it might signify, as al-Tibi said, the succession between night and day and the exclusivity of the administration regarding that succession. This is derived from the daily movement upon which the sphere of action of each of them depends. In al-Kashf, the investigation is that the intent is to explain the succession of each of the sun and the moon in the arrangement of illumination and its dominion independently, as well as the alternation of night and day. Thus it was said: "nor does the night precede the day," as a metonymy for the sign of one preceding the sign of the other; thus, the indication of the alternation was also obtained by integration, as it does not contradict the intent of the reality.

From the necessity of the pairing, this meaning also came regarding the day in His saying, Exalted is He: "It is not for the sun to overtake the moon." And when the "overtaking" was mentioned with the sun, which implies that it is seeking to catch up, it was said "it is not for it" (la yanbaghī) in observance of appropriateness, and the verb was brought to imply renewal. And when the "preceding" was negated in the counterpart, it was emphasized by bringing the purely nominal sentence without the seeking, because it is the sought-after catching-up.

He did not mention the secret in placing the particle of negation upon the sun rather than upon the verb that signifies its attribute, and it is likely to be more concealed than the star Suha. This was so that it might be felt in this rhetorical context that the sun, if left to its own essence, would be non-existent, as is the case with all other possibilities. That which occurs for it only occurs from its Cause, which is the attachment of His power, Exalted is He, to it, according to His complete will, to which nothing in the world of possibility resists. This is highly beneficial in demonstrating that it is subservient in the grip of His disposal, Majestic is He, and there is nothing above that subservience. In this is an emphasis on what is signified by His saying, Exalted is He, "That is the determination of the Exalted in Might, the All-Knowing," and an eloquent refutation of those who attribute effect to it.

It is permissible that this is for the purpose of indicating that it is subservient and nothing is made easy for it except what is intended for it, from the perspective of the subject preceding the verb and placing it after the particle of negation, like [the phrase]: "It is not I who said this" and "It is not Zayd who strove for your need," which signifies specification—i.e., "It is not I who said this, but someone else." The intent of negating the ease of overtaking the moon in its dominion from the sun is the negation that it is made easy for it to eclipse its light and remove its dominion. This returns to the negation of its power to eclipse and remove dominion. Thus, based on the rule of precedence, the meaning is that the sun does not have the power for that, but someone else has power over it, and that is Allah the Exalted. This, after establishing its "running" by the determination of the Exalted in Might, the All-Knowing, intimates that it is subservient and nothing is made easy for it except what is intended for it.

"Each in an orbit swimming" (meaning: they travel within it with expansion; and anyone who is expanded in something is "swimming" in it, and from this is swimming in water). This "course" is in the sky, and there is no obstacle for us in the planet running by itself in the hollow of the sky, while the sky itself remains stationary, not rotating at all. That is by the sky having a hollow filled with air or another subtle body like it, in which the planet runs like the running of a fish in water or a lead ball in a rounded tube, for example; or a hollow free from all else that occupies it; or by the sky as a whole being subtle, or that which is the course of the planet within it being subtle, so the planet splits what is parallel to it and runs as a fish runs in the sea or in a canal of it, while the rest of it has solidified.

The severance of the sphere of air at the sphere of fire that touches the concave of the sphere of the moon—according to the philosophers—and the confinement of subtle bodies to the three elements, the solidity of the sky's mass, the impossibility of piercing and healing for it, and the impossibility of the existence of a vacuum, no evidence has been perfected for any of this. The strongest that is mentioned regarding that are doubts, or they are thinner than a spider's web—and it, by the Lord of the heaven, is the weakest of houses.

It is permissible that the falak (orbit/sphere) refers to a rounded body and the planet within it runs by its running within the thickness of the sky without any rotation of the sky. There is no obstacle to considering this sphere for some planets as the general sphere, and having within it what the astronomers establish to control the different movements of the partial spheres, but one is not forced into that based on Islamic principles, as is not hidden, except that the attribution of "swimming" to the planet has a kind of resistance in its literal sense to this possibility. In the speech of the leading scholars among the Companions and others, there is an allusion to some of what we have mentioned.