قَالَ رَسُولُ اللهِ ﷺ: «مَنْ قَالَ أسْتَغْفِرُ اللهَ العَظِيْمَ الَّذِي لَا إلَهَ إلَّا هُوَ الحَيُّ القَيُّومُ وَ أتُوبُ إلَيْهِ، غَفَرَ للهُ لَهُ، وَ إنْ كَانَ فَرَّ مِنَ الزَّحْفِ»

I seek Allāh's forgiveness, besides whom, none has the right to be worshiped except He, the Ever Living, the Self-Subsisting and Supporter of all, and I turn to Him in repentance.

Reference: I seek Allāh's forgiveness, besides whom, none has the right to be worshiped except He, the Ever Living, the Self-Subsisting and Supporter of all, and I turn to Him in repentance. Abū Dāwud (#1517, 2/85), al-Tirmidhī (#3577, 5/569), al-Hākim (1/511) and he authenticated it and al-Dhahabī agreed with him. Al-Albānī authenticated it, see _Ṣaḥīḥ al-Tirmidhī_ (3/182) and _al-Jāmiʿ al-Uṣūl li-Ahādīth al-Rasūl_ (4/389--390) with research by al-Arnaʾūṭ.