13. Muhammad ibn Tsma‘il has narrated from al-Fadl ibn Shadhan from Ibn Abi ‘Umayr from Mu‘awiyah ibn ‘Ammar who has narrated the following: “I once asked abu ‘ Abd Allah , about the case of a man to whom another man owes a certain amount of dirham and he gives it as a gift to him (the indebted); if he can change his mind and take it back. He (the Imam) said, ‘No, he cannot do so.”’