Pay according to specified measure at specified weight for a specified period

The Prophet Muhammad ﷺ taught the people of Medina that when they pay for goods in advance, they should specify the amount, weight and period of time. This means that if someone pays money to receive something later on, they should make sure that it is clear how much money is being paid, what quantity or weight of goods will be received and when it will be delivered. This way everyone knows exactly what is expected from each other and there are no misunderstandings or disagreements about payment or delivery. It also ensures fairness between both parties involved in the transaction.