As-Salaamu alaykum wa rahmatullaahi wa barakaatuhu
The Excellence of Observing Saum on the Day of 'Ashura'
(i.e., 9th & 10th of Muharram)
Ibn 'Abbas (May Allah be pleased with them) reported: The Messenger of Allah (sallallaahu alayhi wa sallam) observed Saum (fasting) on the day of 'Ashura and commanded us to fast on this day.
[Al-Bukhari and Muslim].
Abu Qatadah (May Allah be pleased with him) reported: The Messenger of Allah (sallallaahu alayhi wa sallam) 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].
Ibn 'Abbas (May Allah be pleased with them) reported: The Messenger of Allah (sallallaahu alayhi wa sallam) said, "If I remain alive till the next year, I shall also observe fast on the ninth of Muharram.''
[Muslim].
The 9th & 10th of Muharram coincides with the Gregorian Calendar to be >>>> Please see following post..