Sunan Ibn Majah, Volume 4, Book 25, Hadith 3117 (DarusSalam) ⓘ

It was narrated from Ibn ‘Abbas that the Messenger of Allah said: “Whoever is in Makkah when the month of Ramadan comes, and he fasts it and prays at night as much as he can, Allah will record for him (reward equivalent to that for) one hundred thousand months of Ramadan observed elsewhere. For each day Allah will record for him (reward equivalent to that for) freeing a slave, and for each day (reward equivalent to that for) providing a horse in the cause of Allah, and for every day merits and for every night merits.”

حَدَّثَنَا مُحَمَّدُ بْنُ أَبِي عُمَرَ الْعَدَنِيُّ، حَدَّثَنَا عَبْدُ الرَّحِيمِ بْنُ زَيْدٍ الْعَمِّيِّ، عَنْ أَبِيهِ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ ‏ "‏ مَنْ أَدْرَكَ رَمَضَانَ بِمَكَّةَ فَصَامَ وَقَامَ مِنْهُ مَا تَيَسَّرَ لَهُ كَتَبَ اللَّهُ لَهُ مِائَةَ أَلْفِ شَهْرِ رَمَضَانَ فِيمَا سِوَاهَا ‏.‏ وَكَتَبَ اللَّهُ لَهُ بِكُلِّ يَوْمٍ عِتْقَ رَقَبَةٍ وَكُلِّ لَيْلَةٍ عِتْقَ رَقَبَةٍ وَكُلِّ يَوْمٍ حُمْلاَنَ فَرَسٍ فِي سَبِيلِ اللَّهِ وَفِي كُلِّ يَوْمٍ حَسَنَةً وَفِي كُلِّ لَيْلَةٍ حَسَنَةً ‏" ‏ ‏.‏