He said that the Prophet used to teach them to say when afflicted by fever or any pain, "In the name of God, the Great, I seek refuge in God, the Mighty, from the evil of every vein that bleeds and from the evil of the heat of hell.”Tirmidhi transmitted it, but said this was a gharib tradition which he knew only among the traditions of Ibrahim b. Isma'il who is declared to be weak in tradition.