Sayyiduna al-Bara' (may Allah be pleased with him) said: When this verse was revealed: "Not equal are those of the believers who sit (at home) and those who strive in the path of Allah" [Surah al-Nisa: 95], the Messenger of Allah (peace and blessings be upon him) commanded Sayyiduna Zayd (may Allah be pleased with him), and he wrote it down. Then Ibn Umm Maktum (may Allah be pleased with him) came and presented the excuse of his ailment and the like to the Messenger of Allah (peace and blessings be upon him), so Allah Almighty revealed the part: "other than those with a disability."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 17814