We’re told that it is not recommended to fast on the days of Ashura, but a sunni pointed out some of our ahadith that say otherwise. They are as follows:

-Sa’ad bin ‘Abdullah from abu Ja’afar from Ja’afar bin Muhammad bin ‘Ubeidullah from ‘Abdullah bin Maymoun al-Qaddah from Imam Ja’afar from his father (as): “The fasting of ‘Ashura removes the sins of a year.”
(Tahtheeb al-Ahkam 4/375 & Wasael al-Shia 10/457).[Grading: Sahih(authentic) as per al-Khoie].

-from Ya’aqoub bin Yazid, from abu Hamam, from Imam abu al-Hassan (as): “The messenger peace be upon him and his household fasted the day of ‘Ashura.”
(Tahtheeb al-Ahkam 4/375).[Grading: Muawaththaq (reliable) as per al-Majlisi].

Could you please shed some light on this?

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