Reporting his father, Imam al-Sadiq (a.s) says, “A needy came to the Holy Prophet asking for help. The Holy Prophets asked, “Is there anyone here to give an interest-free loan?” A man from the Ansar rose up saying, “I have such a loan.” The Holy Prophet said, “Give four vessels of date to this man.” The man did so and came to the Holy Prophet after sometime asking for the payment of his loan. The Holy Prophet said, “We will pay it in the coming days.” The man came another time, hearing the same words. But when he came for the third time, the Holy Prophet smiled and said, “Is there anyone here to give an interest-free loan?” A man rose up saying, “O Allah’s Messenger! I have it.” The Holy Prophet asked, “How much is that?” The man said, “As much as you wish!” The Holy Prophet said, “Give eight vessels of date to this man.” The man said, “You owe me only four vessels.” The Holy Prophet said, “The other four vessels too are for you.” (Qurb al-Isnad: 44 )