Sahih al-Bukhari 4639
Sahih al-Bukhari · Book 65: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)) · Manna and quails
Narrated Sa`id Ibn Zaid:
حَدَّثَنَا مُسْلِمٌ ، حَدَّثَنَا شُعْبَةُ ، عَنْ عَبْدِ الْمَلِكِ ، عَنْ عَمْرِو بْنِ حُرَيْثٍ ، عَنْ سَعِيدِ بْنِ زَيْدٍ ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " الْكَمْأَةُ مِنَ الْمَنِّ وَمَاؤُهَا شِفَاءُ الْعَيْنِ " .
The Prophet (ﷺ) said, "Al-Kam'a is like the Mann (sweet resin or gum) (in that it grows naturally without human care) and its water is a cure for the eye diseases."