certitude
They are the ones overwhelmed by the (true) knowledge of certitude, and have made it easy for themselves to tread on the path which men in luxury found difficult. They derive pleasure and enjoyment from things which repel the ignorant. Though they live on earth with their bodies, their souls hang onto the higher plane. They are the (true) representatives of Allah on His earth, and the ones who invite (people) to His religion. (Imam Ali (AS) attributed in Al Amali, ch. 29, #3)