"As the sun sets, you shall surely return the pledge to him"Deuteronomy 24:13.

A creditor is commanded to return a debt collateral to its Jewish owner when he is in need of it. If the collateral is an item he needs during the daytime – e.g., the tools of his trade or an article of clothing – the creditor must return it to the debtor every day, and only take possession of it during the nighttime. If the collateral is an item needed by night – e.g., linens, blankets or pajamas – he must return it at night and only take possession of it again in the morning.