Al-Muwatta de Malik, 666

On rapporta à Malek, que Omar Ibn Al-Khattab a envoyé dire à Al-Hareth Ibn Hicham: «Demain, c'est le jour de Achoura, jeûne-le et ordonne ta famille de faire pareillement». Chapitre XII Du jeûne des deux jours le fitr et al-adha, et du jeûne omnitemporel

Yahya related to me from Malik that he had heard that Umar ibn al-Khattab had sent (the following message) to al-Harith ibn Hisham, ''Tomorrow is the day of Ashura, so fast (it) and tell your family to fast (also)