Provision is understood in the sense of the source, and in the sense of what is provided. If you intend the source, you would use it in a context like his saying: 'or feeding a poor person,' meaning: he cannot provide anything. If you intend the provided, it would be something in place of it, meaning a little. It may also serve as an affirmation of 'he cannot possess': that is, he does not own anything of ownership. 'From the heavens and the earth' serves as a connection to provision if it is a source, meaning: he does not receive rain from the heavens, nor vegetation from the earth. Or it is an attribute if it is a name for what is provided. The pronoun in 'and they cannot' refers to them, as it relates to the meaning of deities, after it was said 'he does not possess' in the wording. It may also refer to the disbelievers, meaning: and these cannot do anything from that, even though they are alive and capable, so how about the inanimate that has no ability in it.

If you say: what is the meaning of 'and they cannot' after the saying 'he does not possess'? Are they not the same? I say:

There is no implied return in 'and they cannot,' rather the meaning is: they do not possess the ability to provide, and the ability is entirely negated from them, because they are lifeless, unless the return is intended, and the combination of negating possession and ability is for emphasis, or it is intended that they do not possess provision and they cannot own it, nor can it be achieved from them, nor is it correct.