The Prophet ﷺ as saying: If anyone fasts during Ramadan because of faith and in order to seek his reward from Allah, his previous sins will be forgiven to him. If anyone prays in the night of the power (lailat al-qadr) because of faith and in order to seek his reward from Allah his previous sins will be forgiven for him. Abu Dawud said: This tradition has been transmitted in a similar manner by Yahya b. Abi Kathir and Muhammad b. 'Amr from Abu Salamah. (Using translation from Abū Dāʾūd 1372)  

أَنَّ رَسُولَ اللهِ ﷺ قَالَ «مَنْ قَامَ رَمَضَانَ إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ وَمَنْ قَامَ لَيْلَةَ الْقَدْرِ إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ»  

The Prophet ﷺ said, "Whoever established prayers on the night of Qadr out of sincere faith and hoping for a reward from Allah, then all his previous sins will be forgiven; and whoever fasts in the month of Ramadan out of sincere faith, and hoping for a reward from Allah, then all his previous sins will be forgiven." (Using translation from Bukhārī 1901)  

قَالَ رَسُولُ اللهِ ﷺ «مَنْ قَامَ شَهْرَ رَمَضَانَ إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ وَمَنْ قَامَ لَيْلَةَ الْقَدْرِ إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ»  

[Machine] On the authority of the Messenger of Allah ﷺ that he mentioned Ramadan and honored it above the other months, and he said, "Whoever stands in prayer during Ramadan out of faith and seeking reward, his previous sins will be forgiven as if he were born today." Abu Abdur Rahman said, "This is incorrect, and the correct wording is what we mentioned previously." Ishaaq ibn Ibrahim narrated to us, who said Narrated to us An-Nadr ibn Shumeil, who said Narrated to us Al-Qasim ibn Al-Fadl, who said Narrated to us An-Nadr ibn Shayban, from Abu Salamah, who mentioned something similar and said, "Whoever fasts it and stands in prayer during it out of faith and seeking reward."  

عَنْ رَسُولِ اللهِ ﷺ أَنَّهُ ذَكَرَ رَمَضَانَ فَفَضَّلَهُ عَلَى الشُّهُورِ وَقَالَ «مَنْ قَامَ رَمَضَانَ إِيمَانًا وَاحْتِسَابًا خَرَجَ مِنْ ذُنُوبِهِ كَيَوْمِ وَلَدَتْهُ أُمُّهُ» قَالَ أَبُو عَبْدِ الرَّحْمَنِ هَذَا غَلَطٌ وَالصَّوَابُ مَا تَقَدَّمَ ذِكْرُنَا لَهُ 2530 أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ قَالَ أَخْبَرَنَا النَّضْرُ بْنُ شُميلٍ قَالَ حَدَّثَنَا الْقَاسِمُ بْنُ الْفَضْلِ قَالَ حَدَّثَنَا النَّضْرُ بْنُ شَيْبَانَ عَنْ أَبِي سَلَمَةَ فَذَكَرَ مِثْلَهُ وَقَالَ «مَنْ صَامَهُ وَقَامَهُ إِيمَانًا وَاحْتِسَابًا»  

"I said to Abu Salamah bin 'Abdur-Rahman: 'Tell me of something that you heard from your father, that he heard from the Messenger of Allah, with no one in between your father and Messenge of Allah concerning the month of Ramadan. He said: 'Yes; my father said: The Messenger of Allah said: Allah, may He be blessed and exalted, enjoined the fast of Ramadan upon you, and I have made it Sunnah for you to spend its nights in prayer. Whoever fasts it and spends its nights in prayer out of faith and in the hope of reward, he will emerge from his sins as on the day his mother bore him."' (Daif) (Using translation from Nasāʾī 2210)  

حَدِّثْنِي عَنْ شَيْءٍ سَمِعْتَهُ مِنْ أبِيكَ سَمِعَهُ أَبُوكَ مِنْ رَسُولِ اللهِ ﷺ لَيْسَ بَيْنَ أَبِيكَ وَبَيْنَ رَسُولِ اللهِ ﷺ أَحَدٌ فِي شَهْرِ رَمَضَانَ قَالَ نَعَمْ حَدَّثَنِي أَبِي قَالَ قَالَ رَسُولُ اللهِ ﷺ «إِنَّ اللهَ فَرَضَ صِيَامَ رَمَضَانَ وَسَنَنْتُ لَكُمْ قِيَامَهُ فَمَنْ صَامَهُ وَقَامَهُ إِيمَانًا وَاحْتِسَابًا خَرَجَ مِنْ ذُنُوبِهِ كَيَوْمِ وَلَدَتْهُ أُمُّهُ»