Hadith 2

Sahih Bukhari

Book 30: Fasting

Chapter 1

Fasting is obligatory in (the month of) Ramadan

باب وُجُوبِ صَوْمِ رَمَضَانَ

And the Statement of Allah تعالى: “O, you who believe! Observing As-Saum (the fasting) is prescribed for you as it was prescribed for those before you, that you may become Al-Muttaqin.” [V.2:183].
وَقَوْلِ اللَّهِ تَعَالَى: {يَا أَيُّهَا الَّذِينَ آمَنُوا كُتِبَ عَلَيْكُمُ الصِّيَامُ كَمَا كُتِبَ عَلَى الَّذِينَ مِنْ قَبْلِكُمْ لَعَلَّكُمْ تَتَّقُونَ}.
Sahih al-Bukhari 1892
حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا إِسْمَاعِيلُ، عَنْ أَيُّوبَ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ صَامَ النَّبِيُّ صلى الله عليه وسلم عَاشُورَاءَ، وَأَمَرَ بِصِيَامِهِ‏.‏ فَلَمَّا فُرِضَ رَمَضَانُ تُرِكَ‏.‏ وَكَانَ عَبْدُ اللَّهِ لاَ يَصُومُهُ، إِلاَّ أَنْ يُوَافِقَ صَوْمَهُ‏.‏
Ibn `Umar:

The Prophet (ﷺ) observed the fast on the 10th of Muharram ('Ashura), and ordered (Muslims) to fast on that day, but when the fasting of the month of Ramadan was prescribed, the fasting of the 'Ashura' was abandoned. `Abdullah did not use to fast on that day unless it coincided with his routine fasting by chance.