Sunan Ibn Majah 164
It was narrated from 'Abdul-Muhaimin bin 'Abbas bin Sahl bin Sa'd from his father, from his grandfather, that:
The Messenger of Allah said: "The Ansar are an inner garment and the people are an outer garment. If the people were to head towards one valley or a narrow mountain pass and the Ansar towards another, I would travel to the valley of the Ansar, and were it not for the Hijrah, I would have been a man from among the Ansar."
حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا ابْنُ أَبِي فُدَيْكٍ، عَنْ عَبْدِ الْمُهَيْمِنِ بْنِ عَبَّاسِ بْنِ سَهْلِ بْنِ سَعْدٍ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، أَنَّ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ قَالَ ‏
"‏ الأَنْصَارُ شِعَارٌ وَالنَّاسُ دِثَارٌ وَلَوْ أَنَّ النَّاسَ اسْتَقْبَلُوا وَادِيًا - أَوْ شِعْبًا - وَاسْتَقْبَلَتِ الأَنْصَارُ وَادِيًا لَسَلَكْتُ وَادِيَ الأَنْصَارِ وَلَوْلاَ الْهِجْرَةُ لَكُنْتُ امْرَأً مِنَ الأَنْصَارِ ‏"‏ ‏.‏