We were in a Ghazwa (Sufyan once said, in an army) and a man from the emigrants kicked an Ansari man (on the buttocks with his foot). The Ansari man said, "O the Ansar! (Help!)" and the emigrant said. "O the emigrants! (Help!) Messenger of Allah ﷺ heard that and said, "What is this call for, which is characteristic of the period of ignorance?" They said, "O Messenger of Allah ﷺ! A man from the emigrants kicked one of the Ansar (on the buttocks with his foot)." Messenger of Allah ﷺ said, "Leave it (that call) as is a detestable thing." ʿAbdullah bin Ubai heard that and said, 'Have the (the emigrants) done so? By Allah, if we return Medina, surely, the more honorable will expel therefrom the meaner." When this statement reached the Prophet. ʿUmar got up an, said, "O Messenger of Allah ﷺ! Let me chop off the head of this hypocrite (ʿAbdullah bin Ubai)!" The Prophet ﷺ said "Leave him, lest the people say that Muhammad kills his companions." The Ansar were then more in number than the emigrants when the latter came to Medina, but later on the emigrant increased. (Using translation from Bukhārī 4905)   

كُنَّا مَعَ النَّبِيِّ ﷺ فِي غَزَاةٍ فَكَسَعَ رَجُلٌ مِنَ الْمُهَاجِرِينَ رَجُلًا مِنَ الْأَنْصَارِ فَقَالَ الْأَنْصَارِيُّ يَا لِلْأَنْصَارِ وَقَالَ الْمُهَاجِرِيُّ يَا لِلْمُهَاجِرِينَ فَسَمِعَ بِذَلِكَ النَّبِيُّ ﷺ فَقَالَ «مَا بَالُ دَعْوَى الْجَاهِلِيَّةِ؟» قَالُوا يَا رَسُولَ اللهِ رَجُلٌ مِنَ الْمُهَاجِرِينَ كَسَعَ رَجُلًا مِنَ الْأَنْصَارِ قَالَ رَسُولُ اللهِ ﷺ دَعُوهَا فَإِنَّهَا مُنْتِنَةٌ فَسَمِعَ بِذَلِكَ عَبْدُ اللهِ بْنُ أَبِي وَكَانَ مَعَهُمْ فِي الْغَزَاةِ فَقَالَ «أَوْ قَدْ فَعَلُوهَا وَاللهِ لَئِنْ رَجَعْنَا إِلَى الْمَدِينَةِ لَيُخْرِجَنَّ الْأَعَزُّ مِنْهَا الْأَذَلَّ فَقَامَ عُمَرُ» فَقَالَ يَا رَسُولَ اللهِ «دَعْنِي أَضْرِبْ عُنُقَ هَذَا الْمُنَافِقَ» قَالَ رَسُولُ اللهِ ﷺ «لَا يَتَحَدَّثُ النَّاسُ أَنَّ مُحَمَّدًا يَقْتَلُ أَصْحَابَهُ»