Zuhair al-Babi said: Allah has servants whose souls would tremble when they mention Him out of glorification and longing, and other servants whose hearts would beat out of fear and awe. If they were tortured by fire, they would not feel the fire. Other servants would mention Allah in cold winter, yet they would sweat a lot out of fearing Him. Others would mention Allah, and their colors would darken, while others would be sleepless for mentioning Him.