How can it be classed as authentic hadith despite it coming from sahih muslim.. How can Prophet Muhammad PBUH say stuff about Muharram or Ashura or 10th of Muharram as particular when Prophet Muhammad PBUH died before the event of Karbala even took place?
We are not fasting because of Karbala. Ashura is a day of forgiveness from Allah, tha day He saved Bani Israel from the Pharoah