Surah 64:17:
If you loan Allah a goodly loan, He will multiply it for you and forgive you. And Allah is Most Appreciative and Forbearing.
The Commercial Vocabulary:
The text relies heavily on the language of merchants and trade to frame spiritual salvation. The title of the Surah itself, At-Taghabun, is a commercial Arabic term denoting a bad transaction, a raw deal, or a mutual cheating in a marketplace sale.
The State Funding Mechanism:
Written during a period of intense military preparation in Medina, the state was constantly running out of liquid capital to buy weapons, horses, armor, and supplies for upcoming campaigns.
By branding financial donations to Muhammad's treasury as a literal "good loan to Allah" that will yield multiplied financial and spiritual dividends, the text successfully transforms taxation into a religious transaction.
It leverages the commercial anxieties of 7th-century Arabian traders, warning them that keeping their cash instead of funding the army is the ultimate "bad deal" (Taghabun) on Judgement Day.