It is narrated from Ibn Abbas (may Allah be pleased with him), he said: "I bear witness that Allah Almighty has declared the sale of Salam (advance payment for deferred delivery) for a fixed term permissible in His Book and has also granted permission for it." Then he recited this verse: "O you who believe! When you contract a debt for a fixed term..." (__QUR_N__: Al-Baqarah: 282)
Hadith Referenceمسند الإمام الشافعي / كتاب البيوع / 1437
Hadith Takhrijاخرجه عبد الرزاق، رقم : 14064 - والبيهقي: 6 / 19 ، 18 - وفى المعرفة السنن والآثار له (3558) - ابن ابی شيبة (22312) وصححه الحاكم : (2/ 86)۔
It is narrated from Ibn Abbas (may Allah be pleased with him) that when the Prophet (ﷺ) came to Madinah, people used to conduct Salam transactions in dates for one or two years, and sometimes the word three was also mentioned. So the Prophet (ﷺ) said: "Whoever does a Salam sale should do so with a specified measure and specified weight, for a specified period." Imam Shafi’i (may Allah have mercy on him) said: "Just as I have narrated the hadith, I memorized it after hearing it several times from Sufyan."
Hadith Referenceمسند الإمام الشافعي / كتاب البيوع / 1438
Hadith Takhrijاخرجه البخارى البيوع، باب السلم في وزن معلوم (2240) ومسلم ، المساقاة، باب السلم (1604)۔
He told me, whom I trust, he narrated from Sufyan, and he said just as I have said, and regarding the period he said: "That the period should be known."
Hadith Referenceمسند الإمام الشافعي / كتاب البيوع / 1439
Hadith Takhrijاخرجه البخارى البيوع، باب السلم في وزن معلوم (2240) ومسلم ، المساقاة، باب السلم (1604)۔
It is narrated from Ibn Abbas (may Allah be pleased with him), he said: "When the Messenger of Allah (ﷺ) came to Madinah, the people of Madinah used to conduct Salam sales in dates for one, two, or three years. Then the Messenger of Allah (ﷺ) said: 'Whoever does a Salam sale, let him do so for a specified measure, a specified weight, and a specified term.'"
Hadith Referenceمسند الإمام الشافعي / كتاب البيوع / 1440