Sa’ad from Muhammad ibn al-Husayn from Musa ibn Sa’adan from al-Husayn ibn Hammad from Ishaq ibn Ammar from someone who narrated to him from Abu Abdillah عليه السلام, peace be upon him: Imam al-Sadiq عليه السلام said: “One who fears a wild beast, or fears an enemy that may attack him, or fears thieves; he performs the obligatory prayer on his mount by gesturing (ima’a).”