Tafsir of Al-Hadeed 57:7

"Believe in Allah and His Messenger and spend out of that in which He has made you successors" (meaning: He, Glorified be He, has made you successors on His behalf—Mighty and Majestic is He—in disposing of it, without you truly owning it. The Almighty—His status is exalted—has expressed by this what is in their hands of wealth, in order to establish the truth and to encourage spending. For whoever knows that it belongs to Allah the Exalted, and that he is merely in the position of an agent who spends it on the avenues of expenditure designated by Allah the Exalted, finds spending it easy. Or, it means: He has made you successors to those who were before you in what was in their hands, and it has transferred to you. In this, there is also an encouragement to spend and an ease in doing so, because whoever knows that it did not remain with the one before him and has transferred to him, knows that it will not last for another, so it becomes easy for him to give it away, and he becomes desirous of earning the reward by spending it. It suffices you to hear the saying of people regarding what you possess: 'This was once for so-and-so.' In the Hadith: 'The son of Adam says: My wealth, my wealth! And do you have from your wealth anything other than what you ate and consumed, or wore and wore out, or gave in charity and sent ahead?'

The first interpretation is more appropriate for His saying—Exalted be He: 'To Him belongs the dominion of the heavens and the earth.' According to this is what is narrated: it was said to a Bedouin, 'To whom do these camels belong?' He replied, 'They are Allah’s, in my possession.' The saying of the poet also inclines toward this: 'Wealth and family are nothing but deposits, and one day the deposits must be returned.' The verse, according to what is narrated from al-Dahhak, was revealed regarding Tabuk, so do not be heedless.

"So those who have believed among you and spent"—according to what they were commanded—"for them"—because of that—"will be a great reward."

There are hyperboles in this promise that are not hidden, as the sentence is nominal, whereas the apparent form should have been verbal in response to the command—for instance, to say: 'Believe in Allah and His Messenger and spend, [and] you will be given a great reward.' The mention of belief and spending was repeated instead of saying, 'Whoever does that will have a great reward.' It deviated from 'And for those who believed among you and spent is a reward' to what is in the noble arrangement. It magnified the reward by using the indefinite form, and described it as 'great,' and His saying—Mighty and Majestic is He—...