(20) باب فِي الرُّخْصَةِ فِي الْقُعُودِ مِنَ الْعُذْرِ
Zaid bin Thabit said "I was beside the Apostle of Allaah(ﷺ) when the divinely-inspired calmness overtook him and the thigh of the Apostle of Allaah(ﷺ) fell on my thigh. I did not find any weightier than the thigh of the Apostle of Allaah(ﷺ). He then regained his composure and said "Write down. I wrote on a shoulder. Not equal are thise believers who sit (at home), other than those who have a (disabling) hurt, and those who strive in the way of Allaah. When Ibn Umm Makhtum who was blind heard the excellence of the warriors. He stood up and said "Apostle of Allaah(ﷺ) how is it for those believers who are unable to fight (in the path of Allaah)? When he finished his question his divinely-inspired calmness overtook him, and his thigh fell on my thigh and I found its weight the second time as I found the first time." When the Apostle of Allaah(ﷺ) regained his composure, he said "Apostle of Allaah(ﷺ) said "Other than those who have a (disabling hurt). Zaid said "Allaah, the exalted, revealed it alone and I appended it." By Him in Whose hands is my life, I am seeing, as it were the place where I put it (i.e., the verse) at the crack in the shoulder."
Reference: Sunan Abi Dawud 2507
In-book reference: Book 15, Hadith 31
English translation: Book 14, Hadith 2501