Tafsir of As-Saffat 37:112

Nabiyya (as a prophet) is a hal (state) of Isaac; likewise is the Almighty’s saying, min as-salihin (from among the righteous). In this is an exaltation of the status of righteousness. Its postponement hints that it is the ultimate goal of those qualities, as it encompasses the meaning of perfection and completion. The intent of both [prophethood and righteousness] is the performance of good and sound deeds; in usage, [the term salihin] is specific to this.

It has been permitted that min as-salihin is a hal, and that nabiyya is a hal from the pronoun latent within it. It was advanced in the wording for the sake of emphasis and so that the ends of the verses would not be disrupted—though there is a degree of remoteness in this. Furthermore, the permissibility of advancing the hal absolutely, or its uniformity in a structure such as this, is a matter of discussion not hidden from one who has reviewed the Alfiyyah and its commentaries, and it contains what it contains [of controversy]. It has also been permitted that it [the phrase min as-salihin] is in the position of an adjective for nabiyya. The discussion regarding the first [interpretation]—which is what the majority hold—is more commendatory, as is not hidden.

The meaning is his being a prophet and his being among the righteous in the decree and predestination of the Almighty; that is, it was decreed that he would be a prophet, and decreed that he would be among the righteous. If you wish, say "predestined." They are not, in this regard, of the hal al-muqaddarah (the estimated/future state) which is mentioned in contrast to the muqaranah (concurrent state); rather, in this consideration, they are concurrent states to the agent, which is the verb of giving glad tidings, or something else omitted. That is: "We gave him glad tidings of the existence of Isaac, [as] a prophet..."

More than one scholar has necessitated the estimation of such [an omitted word], arguing that glad tidings do not attach to concrete entities (a’yan), but rather to meanings. This has been countered: if it is meant that it is not used except in connection to concrete entities, then the reality is to the contrary—as in [the verse], "When one of them is given glad tidings of [the birth of] a female." If it is said that this is only valid through the estimation of "birth" or similar meanings, then that is the point of contention and there is no basis for that [objection]. That to which the heart inclines is that the meaning rests upon the intention of that [existence], and it may be claimed that the meaning of glad tidings necessitates the estimation of a meaning. It has also been said that they are both hal muqaddarah (estimated states), as in the Almighty’s saying: "Enter it, [being] eternal [therein]." In this, there is a point of investigation.