Sayyiduna Abdullah bin Abbas (may Allah be pleased with them) narrates that when the Prophet Muhammad (peace and blessings be upon him) arrived in Madinah, the people there used to conduct Salam (forward sale) transactions in fruits for two or three years. So the Messenger of Allah (peace and blessings be upon him) said: "In Salam transactions of fruits, specify the measure and the weight."

Ibn Abi Mujalid (may Allah have mercy on him) says that there was a difference of opinion between Abdullah bin Shaddad and Abu Burdah regarding the permissibility of Salam sale. They sent me to Abdullah bin Abi Awfa (may Allah be pleased with him) to ask about it. I asked him, and he said: During the time of the Messenger of Allah (peace and blessings be upon him), Abu Bakr (may Allah be pleased with him), and Umar (may Allah be pleased with him), we used to conduct Salam sales of wheat, barley, raisins, and dates with those who did not possess these items. Then I asked Ibn Abza, and he gave the same answer.

Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates that the Noble Prophet (peace and blessings be upon him) said: "The buyer and the seller have the option (to cancel the transaction) as long as they have not separated from each other, unless their sale is one with the option (of choice)."

Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates that the Noble Prophet (peace and blessings be upon him) said: "When two men engage in a transaction, both of them have the option (to cancel the sale) as long as they do not separate. This is the case if both remain in the same place or if they grant each other the option (of canceling the sale). If they grant each other the option and make the sale on that condition, then the sale will be concluded. (Similarly) if, after making the sale, both separate and neither of them rejects the sale, then the sale also becomes binding."

Sayyiduna Abu al-Wadi’ (may Allah be pleased with him) narrates that we participated in a military expedition, and we camped at a certain place. (During this time) one of our companions sold his horse in exchange for a slave, and then he spent the remaining part of the day and night there until morning. When it was time to depart, the man got up to saddle his horse and regretted (selling the horse). Since the other man had bought the horse, he took hold of it. So both of them went to Sayyiduna Abu Barzah (may Allah be pleased with him) and told him this story. He said:“If I judge between you according to the decision of the Messenger of Allah (peace and blessings be upon him), will you accept it?”The Messenger of Allah (peace and blessings be upon him) said:“The buyer and the seller have the right (to cancel the sale) as long as they have not separated from each other.”

Sayyiduna Abdullah bin Amr (may Allah be pleased with him) narrates that the Noble Prophet (peace and blessings be upon him) said: "The buyer and the seller have the option (to cancel the transaction) as long as they have not separated from each other, unless it is a sale with a stipulated option (i.e., the option to annul the sale has been given). And it is not permissible to separate quickly out of fear that the transaction will be returned."

Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates that the Noble Prophet (peace and blessings be upon him) said:“Whoever buys a Musarrat (an animal whose milk has been retained in its udders), he has the option for three days; if he wishes to return it, he may return it along with a sa’ of grain, but not wheat.”Abu ‘Amir said:“It should not be wheat.”

Sayyiduna Samurah (may Allah be pleased with him) reports that the Noble Prophet (peace and blessings be upon him) said: "If a woman is married off by two guardians, then the first marriage will be valid, and if a man makes a transaction with two men, then the first transaction will be valid."

Sayyiduna Samurah (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: "If two partners sell (an item), then the sale conducted first will be valid, and if two guardians marry off (a woman), then the marriage conducted first will be valid."

Abdur Rahman bin Abdullah bin Mas’ud (may Allah have mercy on him) narrates that Sayyiduna Abdullah bin Mas’ud (may Allah be pleased with him) sold a government slave to Sayyiduna Ash’ath bin Qais (may Allah be pleased with him) for twenty thousand. He brought ten thousand, so Sayyiduna Abdullah bin Mas’ud (may Allah be pleased with him) said:“I sold you this slave for twenty thousand.”He said:“I bought him for ten thousand.”Ash’ath (may Allah be pleased with him) said:“I am content with your opinion in this matter.”Sayyiduna Abdullah bin Mas’ud (may Allah be pleased with him) said:“If you wish, I will narrate to you a hadith of the Messenger of Allah (peace and blessings be upon him).”He said:“Alright (narrate it).”He narrated that the Messenger of Allah (peace and blessings be upon him) said:“When two men make a transaction and there is no witness between them, then (in case of dispute) the statement of the seller will be accepted, or both will cancel the sale.”Ash’ath (may Allah be pleased with him) said:“I return the transaction to you.”