for a single year only, and this is praiseworthy; all of it is authentically attributed to Mālik.
A different report from Ibn al-Qāsim, Ashhab, and Sahnūn states that one must pay zakat for every year that has elapsed, yet they draw a distinction between wealth for which someone bears liability and wealth for which no one does. Thus, when property that had been usurped is restored, they oblige the owner to pay zakat for just one year, whereas for deposits held in trust and any other property for which no guarantor exists, zakat must be paid for all the past years. This is, in their view, the fairest position within the school.
If a person is both a creditor and a debtor, he may offset the debt owed to him against the debt he owes—provided he reasonably expects repayment—and then pays zakat on whatever remains in his possession, so long as it reaches the niṣāb, whether the debt concerns cash or goods.
Should he hold cash equal in amount to what he owes, no zakat is due. If, however, he owns merchandise sufficient to cover that debt, he must still pay zakat on the cash he retains, whether the merchandise is intended for trade or for personal use. Likewise, he may set his debt against the sum his slave under a manumission contract owes him—some say even against the slave’s very person—and similarly against the value (or, according to another view, the service) of a mudabbir slave.
When a person owes a debt yet possesses both merchandise and cash, he offsets the debt with the merchandise and pays zakat on the cash. If the merchandise does not fully meet the debt, he supplements it with enough cash to settle the liability, then pays zakat on whatever surplus remains, provided that surplus reaches the niṣāb after the debt has been deducted.
The same applies if he nets what he owes against what someone else owes him and is left with a surplus subject to zakat: he must pay it. If he has cash on hand equal to his debt, and the year’s end arrives only for the creditor to discharge him of that debt, the jurists hold two views. One opinion—which I prefer—is that he must immediately pay zakat on the cash. The other is that a new lunar year must begin from the moment the debt was lifted.