حَدَّثَنَا يَحْيَى بْنُ أَيُّوبَ، وَقُتَيْبَةُ، وَعَلِيُّ بْنُ حُجْرٍ، قَالُوا حَدَّثَنَا إِسْمَاعِيلُ بْنُ جَعْفَرٍ، عَنْ حُمَيْدٍ، عَنْ أَنَسٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم نَهَى عَنْ بَيْعِ ثَمَرِ النَّخْلِ حَتَّى تَزْهُوَ ‏.‏ فَقُلْنَا لأَنَسٍ مَا زَهْوُهَا قَالَ تَحْمَرُّ وَتَصْفَرُّ ‏.‏ أَرَأَيْتَكَ إِنْ مَنَعَ اللَّهُ الثَّمَرَةَ بِمَ تَسْتَحِلُّ مَالَ أَخِيكَ .

Anas (Allah be pleased with him) reported that Allah's Apostle (PBUH) forbade the sale of the fruit of date-palms until it becomes mellow. We (some of the other narrators in the chain of transmitters) said: What does the word" mellow" mean? He said: (There the fruit) turns red or yellow. Don't you see if Allah had checked (the growth of) fruits; then what for the wealth of your brother would be permissible for you? Translation Not Available

Book reference: Sahih Muslim Book 22 Hadith 3773
Web reference: Sahih Muslim Book 10 Hadith 1555 a