ßÊÇÈ : Hadeeth No:3670 : Sahl bin Sad: The Prophet's companions did not take as a starting date for the Muslim calendar, the day, the Prophet had been sent as an Apostle or the day of his death, but the day of his arrival at Medina....

ßÊÇÈ ÇáÕæã : Hadeeth No:1843 : Ar-Rubi' bint Mu'awadh: "The Prophet sent a messenger to the village of the Ansar in the morning of the day of 'Ashura' (10th of Muharram) to announce: 'Whoever has eaten something should not eat but complete the fast, and whoever is observing the fast should complete it.' "She further said, "Sin...