Tafsir of As-Saffat 37:44

"On thrones" (ala sururin): It is possible that this is a state (hal) referring to the hidden pronoun in "they are honored" (mukramun), or to the [hidden pronoun in the] prepositional phrase preceding it. It is also possible that it is a predicate, in which case the words of the Exalted, "facing each other" (mutaqabilin), would be a state referring to the hidden pronoun within [the thrones] or within "they are honored," or to the prepositional phrase—meaning "in gardens." It may also be related to "facing each other," thus serving as a state for the hidden pronoun in something else.

Their "facing each other" indicates their taking pleasure in one another; some face others for the purpose of enjoyment and conversation. In some Hadith, it is mentioned that the veils are sometimes lifted for them, so they look at one another.

Abu al-Summal read "sururin" with a fathah (vowel sign 'a') on the letter ra, which is a dialect of some [tribes of] Tamim. They open [with a fathah] what is a plural on the pattern of fu'ul from a doubled root if it is a noun. Grammarians differed regarding the adjective; some analogized it to the noun, thus opening it, so they would say dhulalin (docile) with a fathah on the lam according to that dialect. Others restricted this to the noun, which is where the audition [of such usage] occurs.

And His saying, the Exalted...