13 - Muhammad ibn 'Ali informed us, saying: Salih ibn Ahmad narrated to us that his father recounted to him that he said to Ibn al-Kalbi and al-Muzaffar, the two messengers of the Caliph: "I hold the view of obeying him in hardship and ease, in times of willingness and unwillingness, and [even] in instances of preference [given to others over me]. And I am truly regretful for my absence from the congregational prayer, and from my attendance at the Jumu'ah [prayer] and the invitation of the Muslims."