An investigation into jurisprudential rule of * money in assuming the increase in its purchasing power

Cash that its Khums has been paid and is stored in banks in order for business or savings is sometimes faced with an increase in the purchasing power. Some acceptable scientific and jurisprudential comments have been made on the devaluation but no research has been conducted on revaluation. The question is whether Khums is belonged to the increase in the purchasing power. In other words, is the revaluation considered as the quintessence of interest, *, and business so that Khums is belonged to? Given the aforementioned titles being customary in order for Khums belonging, if custom regards the increase as the quintessence of interest, *, and business, Khums is belonged to and if the custom judgment is on non-compliance of the purchasing power increase, Khums is not belonged to that increase. In case of lack of recognition with Ijtihad reasons on the increase in the purchasing power of money, principles of acquittal and presumption explain that Khums is not belonged to the increase in the purchasing power of money. The research assumption is proved in a descriptive-analytical way, by collecting library data, and by utilizing rational methods. The result of the present study is that, considering the fact that the purchasing power of money is the valuation of its nature, Khums is belonged to the increase in the purchasing power because the titles interest, and business are true.