[Machine] Al-Shifa', the daughter of Abdullah, informed me that Labid ibn Rabiah and Adi ibn Hatim, who were among the first immigrants, came to the Medina and entered the mosque. They found Amr ibn al-'As and said, "O son of al-'As, ask permission for us to meet the Commander of the Believers." He replied, "By Allah, you have both got his name right. He is the Commander, and we are the believers." Then Amr ibn al-'As went to Umar and said, "Peace be upon you, O Commander of the Believers." Umar asked, "What is this?" He said, "You are the Commander, and we are the believers." From that day onwards, the title spread.
أَخْبَرَتْنِي الشِّفَاءُ بِنْتُ عَبْدِ اللهِ وَكَانَتْ مِنَ الْمُهَاجِرَاتِ الْأُوَلِ أَنَّ لَبِيدَ بْنَ رَبِيعَةَ وَعَدِيَّ بْنَ حَاتِمٍ قَدِمَا الْمَدِينَةَ وَأَتَيَا الْمَسْجِدَ فَوَجَدَا عَمْرَو بْنَ الْعَاصِ فَقَالَا يَا ابْنَ الْعَاصِ اسْتَأْذِنْ لَنَا عَلَى أَمِيرِ الْمُؤْمِنِينَ فَقَالَ أَنْتُمَا وَاللهِ أَصَبْتُمَا اسْمَهُ هُوَ الْأَمِيرُ وَنَحْنُ الْمُؤْمِنُونَ فَدَخَلَ عَمرٌو عَلَى عُمَرَ فَقَالَ السَّلَامُ عَلَيْكَ يَا أَمِيرَ الْمُؤْمِنِينَ فَقَالَ لَهُ عُمَرُ مَا هَذَا؟ فَقَالَ أَنْتَ الْأَمِيرُ وَنَحْنُ الْمُؤْمِنُونَ فَجَرَى الْكِتَابُ مِنْ يَوْمَئِذٍ