Narrated Anas bin Malik:
The Messenger of Allah ﷺ established an alliance (of brotherhood) between the Emigrants and the Helpers in our house. He was asked: Did not the Messenger of Allah ﷺ say: There is no alliance in Islam ? He replied: The Messenger of Allah ﷺ established an alliance between the Emigrants and the Helpers in our house. This he said twice or thrice.

حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا سُفْيَانُ، عَنْ عَاصِمٍ الأَحْوَلِ، قَالَ سَمِعْتُ أَنَسَ بْنَ مَالِكٍ، يَقُولُ حَالَفَ رَسُولُ اللَّهِ ﷺ بَيْنَ الْمُهَاجِرِينَ وَالأَنْصَارِ فِي دَارِنَا . فَقِيلَ لَهُ أَلَيْسَ قَالَ رَسُولُ اللَّهِ ﷺ " لاَ حِلْفَ فِي الإِسْلاَمِ " . فَقَالَ حَالَفَ رَسُولُ اللَّهِ ﷺ بَيْنَ الْمُهَاجِرِينَ وَالأَنْصَارِ فِي دَارِنَا . مَرَّتَيْنِ أَوْ ثَلاَثًا