Sahih Bukhari Volume 3, Book 46, Hadith 2456

حَدَّثَنَا حَفْصُ بْنُ عُمَرَ، حَدَّثَنَا شُعْبَةُ، عَنْ جَبَلَةَ، كُنَّا بِالْمَدِينَةِ فِي بَعْضِ أَهْلِ الْعِرَاقِ، فَأَصَابَنَا سَنَةٌ، فَكَانَ ابْنُ الزُّبَيْرِ يَرْزُقُنَا التَّمْرَ، فَكَانَ ابْنُ عُمَرَ ـ رضى الله عنهما ـ يَمُرُّ بِنَا فَيَقُولُ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم نَهَى عَنِ الإِقْرَانِ، إِلاَّ أَنْ يَسْتَأْذِنَ الرَّجُلُ مِنْكُمْ أَخَاهُ‏.‏

Narrated By Jabala : "We were in Medina with some of the Iraqi people, and we were struck with famine and Ibn Az-Zubair used to give us dates. Ibn 'Umar used to pass by and say, "The Prophet forbade us to eat two dates at a time, unless one takes the permission of one's companions."