Hazrat Abu Ubaidah narrates that Allah Almighty says: What is wrong with those people who wish to become wise without My worship? They wear the skins of sheep, but their hearts are more bitter than colocynth (a bitter fruit). Are they deceived because of Me, or are they trying to deceive Me? I swear by Myself that I will put them through such a trial in this world that even the forbearing among them will be left astonished and bewildered.