من لا يحضره الفقيه, volume 3, page 232

Hadith.3855 - Al-Hasan bin Mahbub narrated from Ishaq bin Ammar who said: I said to Abu Abdillah (as), "What do you say about a man who gifts his slave one thousand dirhams, or more or less, and says to him, 'Release me from my beating you, or from everything I have done to you, or from the fear and intimidation I caused you?' So the slave releases him and declares him free from blame, desiring what he has been given. Then, later, the master finds the dirhams that he gave the slave in a place where the slave had kept them and takes them. Is it lawful for him?" Imam (as) said: "No." I said: "Is not the slave and his wealth the property of his master?" Imam (as) said: "This is not one of those cases." Then Imam (as) said: "Tell him to return the money to the slave, for it is not lawful for him. He gave it to the slave as a ransom for himself to avoid punishment and retribution on the Day of Judgment." I said: "Does the slave have to pay zakat on it if a year passes over it?" Imam (as) said: "No, unless he invests it in trade. And a slave is not given anything from zakat."

Translation: Bab Ul Qaim Publications — attributed by Thaqalayn·The Arabic above is the original.

Hadith.3856 - It is narrated from Yunus bin Ya'qub who said: I said to Abu Abdillah (as), "A man purchases goods from another man and then asks for them as a gift after the purchase, without compelling him." Imam (as) said: "There is no harm in it."

Translation: Bab Ul Qaim Publications — attributed by Thaqalayn·The Arabic above is the original.

Hadith.3857 - It is narrated from Zayd Al-Shahham who said: I brought a bondwoman to Abu Ja'far Imam Muhammad ibn Ali Al-Baqir (as) to offer her for sale. Imam (as) began to bargain with me, and I bargained with Him (as), and then I sold her to Him (as). He (as) finalized the deal by taking possession through my hand. I said: "May I be your ransom, I was only bargaining with you (as) to see whether bargaining is permissible or not. I then said: 'I have reduced the price for you by ten dinars.'" Imam (as) said: "Far from it! Should this not have been done before finalizing the deal? Have you not heard the saying of the Messenger of Allah (swt) (peace and blessings be upon him and his family): 'Reducing the price after finalization is forbidden?'"

Translation: Bab Ul Qaim Publications — attributed by Thaqalayn·The Arabic above is the original.