Sunan an-Nasa'i, Hadith 4519 ⓘ
; It was narrated from Ibn 'Uar that the Messenger of Allah said: "Do not sell fruits until their condition is known. And he forbade (both) the seller and the purchaser (to engage in such a transaction).
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ " لاَ تَبِيعُوا الثَّمَرَ حَتَّى يَبْدُوَ صَلاَحُهُ " . نَهَى الْبَائِعَ وَالْمُشْتَرِيَ .
also referenced under: Book 44, Hadith 71 (In-Book) & Volume 5, Book 44, Hadith 4523 (DarusSalam)