It was narrated that Qatadah said:"I heard Anas say: 'The Messenger of Allah [SAW] said (Humaid bin Mas'dah said in his Hadith: 'The Prophet of Allah [SAW] said): None of you has believed until he loves for his brother what he loves for himself.'"
أَخْبَرَنَا إِسْحَقُ بْنُ إِبْرَاهِيمَ قَالَ حَدَّثَنَا النَّضْرُ قَالَ حَدَّثَنَا شُعْبَةُ ح وَأَنْبَأَنَا حُمَيْدُ بْنُ مَسْعَدَةَ قَالَ حَدَّثَنَا بِشْرٌ قَالَ حَدَّثَنَا شُعْبَةُ عَنْ قَتَادَةَ قَالَ سَمِعْتُ أَنَسًا يَقُولُ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَقَالَ حُمَيْدُ بْنُ مَسْعَدَةَ فِي حَدِيثِهِ إِنَّ نَبِيَّ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ لَا يُؤْمِنُ أَحَدُكُمْ حَتَّى يُحِبَّ لِأَخِيهِ مَا يُحِبُّ لِنَفْسِهِ
Nesai
The Book Of Faith and its Signs • Hadith 5016