Musnad Ahmad 30:1547

Abdullah ibn Bakr narrated to us, Said ibn Abi Arubah narrated to us, from Qatadah, from Shahr ibn Hawshab, from Abu Hurairah, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "The Ajwa date is from Paradise, and it is a cure for poison. And the truffle is from the Manna, and its water is a cure for the eye."