Sahih Muslim , Book 48, Hadith 45 (In-Book) ⓘ
Abu Malik reported on the authority of his father that when a person embraced Islam, Allah's Messenger used to teach him how to observe prayer and then commanded him to supplicate in these words: " O Allah, grant me pardon, have mercy upon me, direct me to the path of righteousness, grant me protection and provide me sustenance."
حَدَّثَنَا سَعِيدُ بْنُ أَزْهَرَ الْوَاسِطِيُّ، حَدَّثَنَا أَبُو مُعَاوِيَةَ، حَدَّثَنَا أَبُو مَالِكٍ الأَشْجَعِيُّ، عَنْ أَبِيهِ، قَالَ كَانَ الرَّجُلُ إِذَا أَسْلَمَ عَلَّمَهُ النَّبِيُّ صلى الله عليه وسلم الصَّلاَةَ ثُمَّ أَمَرَهُ أَنْ يَدْعُوَ بِهَؤُلاَءِ الْكَلِمَاتِ " اللَّهُمَّ اغْفِرْ لِي وَارْحَمْنِي وَاهْدِنِي وَعَافِنِي وَارْزُقْنِي " .
also referenced under: Hadith 2697 (Reference) & Book 35, Hadith 6515 (USC-MSA)