فَأَتَى النَّبِيَّ صلى الله عليه وسلم رَجُلٌ فَقَالَ: يَا رَسُولَ اللهِ، أَيُّ الدُّعَاءِ أَفْضَلُ؟ قَالَ: سَلِ اللَّهَ الْعَفْوَ وَالْعَافِيَةَ فِي الدُّنْيَا وَالْآخِرَةِ، ثُمَّ أَتَاهُ الْغَدَ فَقَالَ: يَا نَبِيَّ اللهِ، أَيُّ الدُّعَاءِ أَفْضَلُ؟ قَالَ: سَلِ اللَّهَ الْعَفْوَ وَالْعَافِيَةَ فِي الدُّنْيَا وَالْآخِرَةِ، فَإِذَا أُعْطِيتَ الْعَافِيَةَ فِي الدُّنْيَا وَالْآخِرَةِ فَقَدْ أَفْلَحْتَ.
A man came to the Prophet, may Allah bless him and grant him peace, and said, "Messenger of Allah, what is the best supplication?" He answered, "Asking Allah for forgiveness and well-being in this world and the Next world." Then he came to him the following day and asked, "Prophet of Allah, what is the best supplication?" He answered, "Asking Allah for forgiveness and well-being in this world and the Next world. When you are given well-being in this world and the Next, then you have achieved success."
Cited in Al-Adab al-Mufrad (No. 637).