Is using the National Bank Visa card, which allows for purchases and payment of the amount in monthly installments with the bank adding interest on the remaining balance, permissible or forbidden? And is this transaction usurious, or is it like purchasing in installments from merchants?

The aforementioned card is a type of unsecured credit card, and it is not permissible to deal with it as long as the bank charges a usurious interest on the debt incurred by purchases made with it, for the one who consumes usury and the one who feeds it were cursed. It is permissible to issue an unsecured card if its terms do not include a usurious increase on the principal debt. The issuing bank may charge a fixed fee from the customer upon issuance or renewal as a fee for the services provided, and take a commission from the merchant on the customer's purchases, provided that the sale made with the card is at the same price as cash. It is also permissible to withdraw cash from the card as a loan if it does not result in a usurious increase. Any increase beyond the actual services is forbidden because it is usury.