Hadith
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنِ ابْنِ طَاوُسٍ، عَنْ طَاوُسٍ، قَالَ سَمِعْتُ ابْنَ عَبَّاسٍ، يَقُولُ أَمَّا الَّذِي نَهَى عَنْهُ رَسُولُ اللَّهِ صلى الله عليه وسلم أَنْ يُبَاعَ حَتَّى يُسْتَوْفَى الطَّعَامُ .
It was narrated that Tawus said:"I heard Ibn 'Abbas say: 'As for that which the Messenger of Allah forbade, (it is) selling before taking possession of food
Sahih · Abu Ghuddah
Sunan an-Nasa'i 4599 ·Book 44, Hadith 151·Also available on sunnah.com·