Sahih Muslim 2697 c
Abu Malik reported on the authority Of his father that he heard Allah's Messenger (ﷺ) as saying to the person who bad come to him and asked him as to how he should beg his Lord, that he should utter these words:
" O Allah, grant me pardon, have mercy upon me, protect me, provide me sustenance," and he collected his fingers together except his thumb and said: It is in these words (that there is supplication) which sums up for you (the good) of this world and that of the Hereafter.
حَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا يَزِيدُ بْنُ هَارُونَ، أَخْبَرَنَا أَبُو مَالِكٍ، عَنْ أَبِيهِ، أَنَّهُ
 سَمِعَ النَّبِيَّ صلى الله عليه وسلم وَأَتَاهُ رَجُلٌ فَقَالَ يَا رَسُولَ اللَّهِ كَيْفَ أَقُولُ حِينَ أَسْأَلُ
 رَبِّي قَالَ ‏"‏ قُلِ اللَّهُمَّ اغْفِرْ لِي وَارْحَمْنِي وَعَافِنِي وَارْزُقْنِي ‏"‏ ‏.‏ وَيَجْمَعُ أَصَابِعَهُ إِلاَّ الإِبْهَامَ
 ‏"‏ فَإِنَّ هَؤُلاَءِ تَجْمَعُ لَكَ دُنْيَاكَ وَآخِرَتَكَ ‏"‏ ‏.‏