Ruling 1814

If someone has not paid khums from the time he became legally obliged to fulfil religious duties, or if he has not paid khums for a period of time – for example, a number of years – then, if during the year he purchases something that he does not need from profit made by trading and one year passes from the time he started trading – or, if he is not a trader and one year passes from the time he made the profit – he must pay khums on the item. However, if he purchases household furniture and other items that he needs according to his status, it is not necessary for him to pay khums on them provided that he knows that he purchased them during the year in which he made a profit, and he purchased them with the same year’s profit, and he used them in the same year. If he does not know this, then based on obligatory precaution, he must arrive at a settlement (muṣālaḥah) with a fully qualified jurist on an amount that is proportionate to the probability; for example, if he deems it 50% probable that khums on the items is obligatory, then he must pay khums on that 50%.