For the source text click/tap here: Pesachim 31
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A Jew borrowed money from a non-Jew, and left some chametz (think whiskey or vodka) in the non-Jew’s house as a collateral. If after Passover the Jew defaults on the loan, the non-Jew remains in the possession of the chametz as a repayment. We therefore can say that the chametz was already in non-Jewish hand on Passover retroactively, and now it is not forbidden for use.
By contrast, if it was a non-Jew who borrowed the money and left his chametz in the Jewish house, then, if after Passover the non-Jew defaults on his loan, the chametz becomes Jewish retroactively, and is therefore forbidden for use, as chametz owned by a Jew on Passover.
This leads us to the notion of moneylending and the fraught relationship between the Jew and the Aristocracy of Europe in financing among other, things its wars.