“by a single word”—that is, by a word different from the first; and “for one word with another” means with a second, distinct term. Had the author written, “for a single word with a single word,” the intent would have been even clearer, and that is precisely what he means.
So, if someone says regarding the verse, “on the Day when the sky will reel with a reeling” (at-Tur 9), that al-mawr simply means “movement,” he is only approximating, for al-mawr is a light, rapid motion, not just motion in general. Likewise, if he declares that revelation (wahy) is nothing more than “communication,” or explains “We revealed to you” (awḥaynā ilayka) as “We sent down to you,” or takes “We decreed for the Children of Israel” (wa-qaḍaynā ilā Banī Isrāʾīl, al-Isrāʾ 4) to mean “We informed them,” all such renderings are mere approximations, not precise definitions. Revelation is in fact a swift, subtle communication, and “We decreed for them” is more specific than simple notification, for it carries the sense of something sent down to them and inspired within them. The Arabs often let one verb stand in for another, giving it the same transitivity and governing pattern.
Explanation
Those who say that the meaning of “on the Day when the sky will reel with a reeling” is simply “it will move” are speaking approximately, because al-mawr denotes a light, rapid motion rather than any motion whatsoever. The same applies when someone defines revelation as “communication,” as in, “Allah revealed to His Prophet,” meaning “He informed him of such-and-such”; that, too, is only an approximate explanation. Or if someone glosses “We decreed for the Children of Israel” as “We informed them,” that again is approximate, because the phrase “We decreed for them” is narrower in scope than “We informed them”: it conveys a predestined decree that reaches them—it is not merely information. The author makes this clear when he says, “for revelation is a swift, hidden communication, and ‘We decreed for them’ is more specific than ‘We informed,’ for it involves something sent down to them and inspired….”