Samurah bin Jundub said “The war-cry of the Emigrants was ‘Abd Allah and that of the helpers ‘Abd Al Rahman.”  

كَانَ شِعَارُ الْمُهَاجِرِينَ عَبْدُ اللَّهِ وَشِعَارُ الأَنْصَارِ عَبْدُ الرَّحْمَنِ  

Ilyas bin Salamah(bin Al Akwa’) said on the authority of his father “We went on an expedition with Abu Bakr (Allaah be pleased with him) in the time of the Apostle of Allaah ﷺ and our war cry was “Put to death” “Put to death”.”  

غَزَوْنَا مَعَ أَبِي بَكْرٍ ؓ زَمَنَ النَّبِيِّ ﷺ فَكَانَ شِعَارُنَا أَمِتْ أَمِتْ  

Al-Muhallab ibn AbuSufrah said: A man who heard the Prophet ﷺ say: If the enemy attacks you at night, let your war cry be Ha-Mim. They will not be helped.  

سَمِعَ النَّبِيَّ ﷺ يَقُولُ إِنْ بُيِّتُّمْ فَلْيَكُنْ شِعَارُكُمْ حم لاَ يُنْصَرُونَ