Is it permissible to sell fish via the internet, fax, and telephone, requesting an advance payment or opening a letter of credit, knowing that the goods are not purchased until the amount is received, and are not delivered until the container is prepared?

It is permissible to market fish online or by phone if the seller adheres to the Shariah controls, which are: not selling what one does not possess, and not selling a commodity before acquiring it, especially food, which scholars unanimously agree is forbidden to sell before taking possession of it. As for taking money in advance as a pledge (down payment) out of fear of fraud, it is permissible if this money is considered part of the price after the sale is completed, and it is returned to its owners if the sale is not concluded, because it is permissible to take a pledge before a debt is established. However, selling fish before buying and acquiring it is not permissible.