Mishkat al-Masabih
Mishkat al-Masabih 3948
Arabic hadith text
وَعَن الْمُهلب أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: " إِنْ بَيَّتَكُمُ الْعَدُوُّ فَلْيَكُنْ شِعَارُكُمْ: حم لَا ينْصرُونَ ". رَوَاهُ التِّرْمِذِيّ وَأَبُو دَاوُد
Translation
Unreviewed translation. All hadiths in this collection are available in five languages. Titles and introductions may remain in Arabic.
Al-Muhallab reported that the Messenger of God (peace and blessings be upon him) said, ‘If the enemy attacks you at night, let your battle cry be: Ha Mim; they will not be helped.’ Narrated by al-Tirmidhi and Abu Dawud.
Notes and open questions — unreviewed
The source gives the battle cry as the disconnected letters Ha Mim followed by the phrase they will not be helped; the phrase is translated literally.