The Essence
Al-Mu'min is the One who inspires faith (Iman) in the hearts of His servants and provides them with safety and security from fear. He fulfills His promises and grants peace to those who trust in Him.
In the Quran
هُوَ اللَّهُ الَّذِي لَا إِلَهَ إِلَّا هُوَ الْمَلِكُ الْقُدُّوسُ السَّلَامُ الْمُؤْمِنُ الْمُهَيْمِنُ
"He is Allah, other than whom there is no deity, the Sovereign, the Pure, the Perfection, the Bestower of Faith (Al-Mu'min), the Overseer... (Surah Al-Hashr 59:23)"
In Your Duas
اللَّهُمَّ إِنِّي أَسْأَلُكَ الْعَفْوَ وَالْعَافِيَةَ فِي الدُّنْيَا وَالآخِرَةِ
"O Allah, I ask You for forgiveness and security in this world and the Hereafter. O Al-Mu'min, grant me safety from what I fear."
— Sunan Ibn Majah 3871 (Modified with permission from Quran 7:180)