وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ حُمَيْدٍ الطَّوِيلِ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم نَهَى عَنْ بَيْعِ الثِّمَارِ حَتَّى تُزْهِيَ ‏.‏ فَقِيلَ لَهُ يَا رَسُولَ اللَّهِ وَمَا تُزْهِي فَقَالَ ‏"‏ حِينَ تَحْمَرُّ ‏"‏ ‏.‏ وَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ أَرَأَيْتَ إِذَا مَنَعَ اللَّهُ الثَّمَرَةَ فَبِمَ يَأْخُذُ أَحَدُكُمْ مَالَ أَخِيهِ ‏"‏ ‏.‏

Yahya related to me from Malik from Humayd at-Tawil from Anas ibnMalik that the Messenger of Allah, may Allah bless him and grant himpeace, forbade selling fruit until it had become mellow. He was asked,"Messenger ofAllah! What do you mean by become mellow?" He said, "Whenit becomes rosy." The Messenger of Allah, may Allah bless himand grant him peace, added, "Allah may prevent the fruit frommaturing, so how can you take payment from your brother for it." Translation Not Available

Book Ref: Muwatta Imam Malik Book 31 Hadith 1303
Web Ref:  Muwatta Imam Malik Book 31 Hadith 11