Fast of 'Ashura
صِيَامُ يَوْمِ عَاشُورَاءَ أَحْتَسِبُ عَلَى اللَّهِ أَنْ يُكَفِّرَ السَّنَةَ الَّتِي قَبْلَهُ
Siyamu yawmi 'Ashura'a ahtasibu 'ala-llahi an yukaffira-s-sanata-llati qablah.
"Fasting the day of 'Ashura, I hope from Allah that it expiates the year before."
Narrated by Abu Qatadah. Sahih Muslim 1162
A short reflection
The 10th of Muharram. Paired with the 9th for emphasis. An annual rinse.