The Messenger of Allah ﷺ said, "Bring me a shoulder blade or a tablet." He then dictated, "Not equal are those believers who sit at home" [Nisa 4:95], while Amr Ibn Umm Maktum was behind him.Amr asked, "Is there any concession for me?"Then the verse was revealed, "except for those who have a disability" [Nisa 4:95].
أن رسول الله ﷺ قال: إيتوني بالكتف أو اللوح فكتب: {لا يستوي القاعدون من المؤمنين} وعمرو ابن أم مكتوم خلف ظهره، فقال: هل لي من رخصة؟ فنزلت: {غير أولي الضرر}.
Tirmidhi (1670) and Nasai (6/10) both narrated it from Nasr bin Ali Jahdami, who said, Mutamir bin Sulayman informed us, from his father, from Abu Ishaq, from Bara, and he related it. Its isnad is sahih. Ibn Hibban also narrated it through this same route in his Sahih (41).