Sunan Ibn Majah, Hadith 3455 ⓘ
It was narrated that Abu Hurairah said: “We used to narrate from the Messenger of Allah and mention truffles, and they said: ‘(It is) the smallpox of the earth.’ When the Messenger of Allah was told of what they were saying: he said: ‘Truffles are a type of manna, and the Ajwah are from Paradise, and they are a healing from poison.’”
حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا أَبُو عَبْدِ الصَّمَدِ، حَدَّثَنَا مَطَرٌ الْوَرَّاقُ، عَنْ شَهْرِ بْنِ حَوْشَبٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ كُنَّا نَتَحَدَّثُ عِنْدَ رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ فَذَكَرْنَا الْكَمْأَةَ فَقَالُوا هِيَ جُدَرِيُّ الأَرْضِ . فَنُمِيَ الْحَدِيثُ إِلَى رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ فَقَالَ " الْكَمْأَةُ مِنَ الْمَنِّ وَالْعَجْوَةُ مِنَ الْجَنَّةِ وَهِيَ شِفَاءٌ مِنَ السَّمِّ " .
also referenced under: Book 31, Hadith 3582 (In-Book) & Volume 4, Book 31, Hadith 3455 (DarusSalam)