Tafsir of An-Nahl 16:73

"Provision" (al-rizq) can be understood as the verbal noun (the act of providing) or as the object provided (al-marzūq).

• If you intend the verbal noun: You make shay’an (anything) the object of it, as in the verse: "Or feeding on a day of severe hunger" (Al-Balad: 14). The meaning here is: "They do not possess the ability to provide anything."
• If you intend the object provided: Shay’an acts as a substitute for it, meaning "a little." It is also possible that it serves as an emphasis for "they do not possess," meaning: "They do not possess any form of ownership at all."

"From the heavens and the earth":

• If rizq is a verbal noun, this is a connection to it, meaning: "They do not provide rain from the heavens, nor vegetation from the earth."
• If rizq is a noun for what is provided, this is an adjective describing it.

"And they are not able":

• The pronoun refers to "what" (mā) because it carries the meaning of "gods," following the previous mention of "they do not possess" (lā yamliku) which was based on the literal wording.
• It is also possible that it refers to the disbelievers, meaning: "These people, despite being alive, active, and possessing intellect, are unable to do any of that; so how could the inanimate objects, which have no sensation, be able to?"

If you ask: What is the meaning of "and they are not able" after saying "they do not possess"? Are they not the same thing?

I say: In "they are not able," there is no implied referent returning to the subject. The meaning is: They do not possess the ability to provide, and the capacity for it is negated from them entirely because they are dead/inanimate. Alternatively, one might assume a referent, and the combination of negating ownership and ability is for emphasis. Or, it means: They do not possess provision, nor is it possible for them to possess it, nor is it feasible or sound for them to do so.