On a certain evening ‘Ali (a.s.) was departing from the mosque. The surroundings were bright due to the moonlight. He saw behind him a group of people walking towards him. He enquired as to who they were? They said: “We are your Shias.” ‘Ali (a.s.) looked at their faces carefully and said.
“Why is it that your faces do not exhibit any sign of you being a Shia?”.
“Master, what are the signs of a Shia?”
“Their faces are pale due to excessive worship and the fear of Allah, their backs are bent due to prolonged prayers, too much fasting causes their abdomen to touch their backbones, their lips become dry be repeating endless invocations, and their hearts are filled with the fear of Allah.” ( Bihār al-Anwār, Al-Irshad )