Sahih Muslim
Hadith 9798
He who wishes to observe this fast may do so, and he who wishes to abandon it may do so.
Hadith 9799
This hadith is narrated on the authority of Hisham with the same chain of transmitters, but he made no mention in the first part of the hadith that the Messenger of Allah (ﷺ) used to observe fast, and said about the second part that he abandoned the (fast) of Ashura, and he who wished observed the fast and who wished otherwise abandoned it, and he did not hold it as the words of the Messenger of Allah (ﷺ) as mentioned in the narration transmitted by Jarir.
Hadith 9800
'A'isha (Allah be pleased with her) reported. In the pre-Islamic days fast was observed on the day of Ashura, but with the advent of Islam (its position was ascertained as that of a voluntary fast). Then he who wished to fast fasted, and he who liked to abandon it abandoned it.
Hadith 9801
'A'isha (Allah be pleased with her) reported that the Messenger of Allah (ﷺ) had ordered to observe fast (on 'Ashura) before the fasting in Ramadan was made obligatory. But when it became obligatory, then he who wished fasted on the day of Ashura, and he who wished did not observe it (on that day).
Hadith 9802
He who wishes to fast should do so, and he who wishes to break it may do so.
Hadith 9803
'Ashura is one of the days of Allah, so he who wished should observe fast and he who wished otherwise should abandon it.
Hadith 9804
A hadith like this has been narrated on the authority of Abdullah through the same chain of transmitters.
Hadith 9805
That was a day on which the people of pre-Islamic days used to observe fast. So he who amongst you likes to observe fast should do so, and he who does not like it should abandon it.
Hadith 9806
It is a day on which the people of pre-Islamic days observed fast. So he who liked to fast on this day should do so, and he who liked to abandon it should abandon it. 'Abdullah (Allah be pleased with him) did not observe fast except when it coincided (with the days when he was in the habit of observing voluntary fasts during every month).
Hadith 9807
Abdullah b. Umar (Allah be pleased with them) reported that the day of 'Ashura was mentioned before the Messenger of Allah (ﷺ) and he narrated a hadith like one (narrated above).
Hadith 9808
It is a day when the people in the pre-Islamic days need to observe fast, so he who wishes to observe fast should do so, and he who wishes to abandon it should do so.
Hadith 9809
When al-Ash'ath b. Qais entered the house of 'Abdullah he was having his breakfast. He ('Abdullah b. Umar) said: Abd Muhammad (al-Asha'th), come near to the breakfast. Thereupon he said: Is not today the day of 'Ashura? He ('Abd al-Rahman) said: Do you know what the day of 'Ashura is? He said: What is it? He said: It is a day on which the Messenger of Allah (ﷺ) used to observe fast before the (fasting) in the month of Ramadan (became) obligatory. But when it became obligatory the (fasting of 'Ashura) was abandoned (as compulsory). Abu Kuraib said: He (the Holy Prophet) abandoned it.
Hadith 9810
When (fasting) in Ramadan was (made) obligatory, he abandoned it (the practice of observing fast on Ashura).
Hadith 9811
Abu Muhammad, come near and dine. Upon this he said: I am fasting. Thereupon he said: We used to observe fast and then (this practice) was abandoned.
Hadith 9812
Abu Abd al-Rahman, it is the day of 'Ashura (and you are eating). Upon this he said: Fast was observed on (this day) before the (fasting) in Ramadan was made obligatory, but when it was made obligatory, (fasting on the day of 'Ashura) was abandoned. So if you are not fasting, then take food.
Hadith 9813
Jabir b Samura reported that the Messenger of Allah (ﷺ) commanded us to observe fast on the day of Ashura and exhorted us to do it and was particular about it But when (fasting) in Ramadan was made obligatory, he hence. forth neither commanded us nor forbade us, nor was he so particular about it.
Hadith 9814
People of Medina, where are your scholars? I heard the Messenger of Allah (ﷺ) say on this very day: It is the day of 'Ashura. Allah has not made fasting on This day obligatory for you but I am fasting. He who likes to observe fast among you should do so, and he who likes not to observe it may not observe it.
Hadith 9815
A hadith like this has been narrated on the authority of Ibn Shihab through the same chain of transmitters.
Hadith 9816
I am fasting today, so he who wishes to observe fast should do so; but he did not make mention of the rest of the hadith.
Hadith 9817
It is the day on which Allah granted victory to Moses and (his people) Bani Isra'il over the Pharaoh and we observe fast out of gratitude to Him. Upon this the Messenger of Allah (ﷺ) said: We have a closer connection with Moses than you have, and he commanded to observe fast on this day.