The Messenger of Allah ﷺ said, "Whoever grants a Muslim the cancellation of a sale, Allah will overlook his slips."In another narration, "on the Day of Resurrection."
قال رسول الله ﷺ: من أقال مسلما أقاله الله عثرته. وفي رواية: يوم القيامة.
It was narrated by Abu Dawud (3460), Ibn Majah (2199), and Abdullah bin Ahmad (7431), and Ibn Hibban (5030) and Hakim (2/45) both graded it sahih, all of them through the route of Amash, from Abu Salih, from Abu Hurairah. He mentioned it. Its isnad is sahih.It was also narrated by Ibn Hibban (5029), Qudai in Musnad Shihab (453–454), and Bayhaqi (6/27), all of them through the route of Ishaq bin Muhammad Farawi, from Malik bin Anas, from Sumayy, from Abu Salih, with the wording, "Whoever rescinds a sale for a regretful buyer..." adding the word "regretful" into it.As for Ishaq bin Muhammad Farawi, although he is among the narrators of Bukhari, more than one authority of hadith has declared him daif. Nasai said, "He is discarded (matruk)." Daraqutni said, "Daif." The reason for this is that he lost his eyesight, and his memory deteriorated as a result, as Abu Hatim said, "He was truthful, but he lost his sight, so he would sometimes be prompted, though his books were sound." He also said on another occasion, "His hadith is confused." So this addition of his is shadh (anomalous), because no one else followed him in transmitting this addition from Malik. Ibn Hibban pointed to this when he said, "No one narrated this from Malik except Ishaq Farawi."Something of similar meaning has been narrated from Abu Shurayh, who said, the Messenger of Allah ﷺ said, "Whoever rescinds a sale transaction for his brother, Allah will rescind his stumble on the Day of Resurrection." This was narrated by Tabarani in Al-Awsat (893), from Ahmad bin Yahya Hulwani, who said, Saeed bin Sulayman narrated to us, from Sharik, from Abdul-Malik bin Abu Bashir, from Abu Shurayh. He mentioned it.Sharik here is Ibn Abdullah the judge, who had poor memory and requires a corroborator, and I did not find one. Tabarani also confirmed that no one narrated this hadith from Abdul-Malik except Sharik. Furthermore, Abdul-Malik bin Abu Bashir did not narrate from any of the companions, so there is also a break in the chain here. Haythami's statement in Al-Majma (4/110), "Its narrators are trustworthy," does not necessarily establish the soundness of the isnad.