This chapter draws together the most rewarding single days to fast outside Ramadan: the Day of 'Arafah (9th of Dhul-Hijjah), 'Ashura' (10th of Muharram), and Tasu'a (the 9th of Muharram). What unites them is the theme of expiation, fasting these days as a means by which God wipes away sins.
Notice the careful gradation across the reports. 'Arafah carries a larger promise than 'Ashura', and the Prophet's wish to fast the ninth alongside the tenth teaches an attentiveness to how we worship, not only that we worship. The forgiveness mentioned here concerns minor sins; major sins call for sincere repentance, a detail the scholars are careful to preserve.
Hadith 1250
Abu Qatadah (May Allah be pleased with him) reported:
وعن أبي قتادة رضي الله عنه قال: سئل رسول الله صلى الله عليه وسلم: عن صوم يوم عرفة؟ قال: "يكفر السنة الماضية والباقية" ((رواه مسلم)).
The Messenger of Allah (ﷺ) was asked about the observance of Saum (fasting) on the day of 'Arafah. He said, "It is an expiation for the sins of the preceding year and the current year." [Muslim].
In plain words
Fasting the Day of Arafah is described as wiping away the sins of the year before and the year to come. A great reward for a single day.
Reference : Riyad as-Salihin 1250 In-book reference : Book 8, Hadith 260
Hadith 1251
Ibn 'Abbas (May Allah be pleased with them) reported:
وعن ابن عباس رضي الله عنهما أن رسول الله صلى الله عليه وسلم صام يوم عاشوراء، وأمر بصيامه. ((متفق عليه))
The Messenger of Allah (ﷺ) observed Saum (fasting) on the day of 'Ashura' and commanded us to fast on this day. [Al-Bukhari and Muslim].
In plain words
The Prophet fasted on the day of Ashura and told the believers to fast it too, marking it as a recommended day of fasting.
Reference : Riyad as-Salihin 1251 In-book reference : Book 8, Hadith 261
Hadith 1252
Abu Qatadah (May Allah be pleased with him) reported:
وعن أبي قتادة رضي الله عنه أن رسول الله صلى الله عليه وسلم سئل عن صيام يوم عاشوراء فقال: "يكفر السنة الماضية" ((رواه مسلم)).
The Messenger of Allah (ﷺ) was asked about observing As-Saum (the fast) on the tenth day of Muharram, and he replied, "It is an expiation for the sins of the preceding year." [Muslim].
In plain words
Fasting on the tenth of Muharram, the day of Ashura, is described as wiping away the sins of the preceding year.
Reference : Riyad as-Salihin 1252 In-book reference : Book 8, Hadith 262
Hadith 1253
Ibn 'Abbas (May Allah be pleased with them) reported:
وعن ابن عباس رضي الله عنهما قال: قال رسول الله صلى الله عليه وسلم: "لئن بقيت إلى قابل لأصومن التاسع" ((رواه مسلم)).
The Messenger of Allah (ﷺ) said, "If I remain alive till the next year, I shall also observe fast on the ninth of Muharram." [Muslim].
In plain words
The Prophet expressed his wish to also fast the ninth of Muharram alongside the tenth, teaching attentiveness to how we fast these days.
Reference : Riyad as-Salihin 1253 In-book reference : Book 8, Hadith 263