Hadith 2883

Ibn 'Abbas said that when God’s Messenger came to Medina they were paying one, two and three years in advance for fruits, so he said, “Those who pay in advance for anything must do so for a specified measure and weight with a specified time fixed.” (Bukhari and Muslim.)

عَنِ ابْنِ عَبَّاسٍ قَالَ: قَدِمَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ الْمَدِينَةَ وَهُمْ يُسْلِفُونَ فِي الثِّمَارِ السَّنَةَ وَالسَّنَتَيْنِ وَالثَّلَاثِ فَقَالَ: «مَنْ سلف فِي شَيْءٍ فَلْيُسْلِفْ فِي كَيْلٍ مَعْلُومٍ وَوَزْنٍ مَعْلُوم إِلَى أجل مَعْلُوم»

Reference: 5628830
In-book reference: Book 11, Hadith 2883