Hadith 2697 a - The Book Pertaining to the Remembrance of Allah, Supplication, Repentance and Seeking Forgiveness - Sahih Muslim - صحيح مسلم - Collection of Actions, Sayings and Teachings of Prophet Muhammad (صلى الله عليه و سلم) - Kutub as-Sittah

48. The Book Pertaining to the Remembrance of Allah, Supplication, Repentance and Seeking Forgiveness - كتاب الذكر والدعاء والتوبة والاستغفار

10) Chapter: The Virtue Of Tahlil (Saying La Ilaha Ill-Allah), Tasbih (Saying Subhan Allah) And (Du'a) Supplication

Abu Malik Ashaja'i reported on the authority of his father that whenever a person embraced Islam, Allah's Messenger (ﷺ) instructed him to recilte:

" O Allah, grant me pardon, have mercy upon me, direct me to the path of righteousness and provide me sustenance."

Reference: 2697 a
English reference: Book 35, Hadith 6514
In-book reference: Book 48, Hadith 44
Grade: Sahih
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10) باب فَضْلِ التَّهْلِيلِ وَالتَّسْبِيحِ وَالدُّعَاءِ

حَدَّثَنَا أَبُو كَامِلٍ الْجَحْدَرِيُّ، حَدَّثَنَا عَبْدُ الْوَاحِدِ، - يَعْنِي ابْنَ زِيَادٍ - حَدَّثَنَا أَبُو مَالِكٍ الأَشْجَعِيُّ عَنْ أَبِيهِ، قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يُعَلِّمُ مَنْ أَسْلَمَ يَقُولُ ‏‏ ‏.‏ "‏ اللَّهُمَّ اغْفِرْ لِي وَارْحَمْنِي وَاهْدِنِي وَارْزُقْنِي ‏"