Is it permissible to buy and sell currencies at a bank without withdrawing them in cash, with the intention of reselling the foreign currency to the bank later, or receiving it in kind upon the second sale?

The aforementioned transaction is permissible, and constructive possession is realized in it. The intention to sell the purchased currency to the bank later for profit does not affect it, as possession is based on custom (urf). The Islamic Fiqh Academy's resolution states that among the forms of constructive possession considered valid legally and customarily are: the banking entry of a sum of money into the customer's account, and the receipt of a check if it has a withdrawable balance.