In the hadith of Sayyiduna Sa'd bin Abi Waqqas (may Allah be pleased with him) it has already passed that (he said): "During the Farewell Hajj, the Messenger of Allah (peace and blessings be upon him) visited me in an illness by which I had come to the brink of death." Then he mentioned the (whole) hadith about his bequest.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الوصايا / Q12656