It is mentioned in Sharh Nahjul Balagha that during the battle of Siffin, Ali (a.s) used to spread his prayer mat between two rows of fighters and perform the prayers even as arrows rained from all sides and the battle continued to rage. He had not a slight fear of those arrows. Even after the completion of prayers he did not leave his place before reciting additional supplications and devotions. Allamah Ibn Abil Hadid writes that Ali (a.s) was so habitual of recommended prayers (Nafila) and performed such lengthy prostrations that his forehead began to resemble the knee of the camel. He used to be so much engrossed in Prayers that he became absolutely oblivious of everything else. So much so that he was not even aware of his body. It is mentioned that once an arrow pierced his foot but it was very painful to him if someone tried to remove it. So they were advised to wait till Ali (a.s) was engrossed in prayers. Thus when Ali (a.s) was praying, the people removed the arrow and Ali (a.s) was hardly aware of it. Reference :Akhlaq al-A’imma, Morals & Manners of the Holy Imams
Worship Of Imam Ali (a.s)
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