Sahih al-Bukhari, Book 97, Hadith 103 (In-Book) ⓘ
Narrated Abu Huraira: The Prophet said, "None of you should say: 'O Allah! Forgive me if You wish,' or 'Bestow Your Mercy on me if You wish,' or 'Provide me with means of subsistence if You wish,' but he should be firm in his request, for Allah does what He will and nobody can force Him (to do anything).
حَدَّثَنَا يَحْيَى، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، عَنْ مَعْمَرٍ، عَنْ هَمَّامٍ، سَمِعَ أَبَا هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " لاَ يَقُلْ أَحَدُكُمُ اللَّهُمَّ اغْفِرْ لِي إِنْ شِئْتَ، ارْحَمْنِي إِنْ شِئْتَ، ارْزُقْنِي إِنْ شِئْتَ، وَلْيَعْزِمْ مَسْأَلَتَهُ، إِنَّهُ يَفْعَلُ مَا يَشَاءُ، لاَ مُكْرِهَ لَهُ " .
also referenced under: Hadith 7477 (DarusSalam) & Volume 9, Book 93, Hadith 569 (USC-MSA)