Musnad Ahmad 1017:38

Muhammad ibn Ubayd narrated to us, Salih—meaning Ibn Hayyan—narrated to us, from Ibn Buraydah, from his father, that he was with the Messenger of Allah, peace and blessings of Allah be upon him, along with forty-two of his companions. The Prophet, peace and blessings of Allah be upon him, was praying at the Maqam (Station of Ibrahim), and they were sitting behind him waiting for him. When he finished praying, he reached out toward the space between himself and the Kaaba as if he wanted to take something. Then he turned toward his companions, and they rose, but he signaled to them with his hand to sit, so they sat. He said, "Did you see me when I finished my prayer, reaching out toward the space between myself and the Kaaba as if I wanted to take something?" They said, "Yes, O Messenger of Allah." He said, "Paradise was presented to me, and I have not seen anything like what is in it. A cluster of grapes passed by me, and it pleased me, so I reached out to take it, but it moved ahead of me. Had I taken it, I would have planted it among you so that you could eat from the fruit of Paradise. Know that the truffle is a cure for the eye, and that the Ajwa date is from the fruit of Paradise, and that this black seed which is in the salt—know that it is a cure for every disease except death."