Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrates: Once the Prophet Muhammad (peace and blessings be upon him) came to us, and in his blessed hand was a truffle. He (peace be upon him) said: "This is a part of the manna that was sent down upon the Children of Israel, and its water is a cure for the eyes."
Hadith Referenceصحیح ابن حبان / كتاب الطب / 6074
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح - «الضعيفة» تحت الحديث (2918).فضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده صحيح على شرط البخاري