Imam Ibnul Qaiyam Al Jawziyh relates in one of his books, the incident between prophet Nuh (PBUH) and Shaytan. After some discussion the Shaytan addresses Nuh (PBUH) saying i have led all those people who are not on your bout to hell forever by using two of my common and most successful tricks..... The two tricks the devil uses on most people to lead them astray are Jealousy and the Love of the Dunya (world). Jealousy is a grave sin as this was the cause of Shaytan_s downfall in front of Adam (PBUH) when he refused to bow down, as he was jealous of him. This was the first sin which was commited in the heavens. The first sin commited on earth was also jealousy, as Kabil kills his brother out of jealousy. This is what happened, it gives us a great lesson for us to cure our selves from this evil diease which most of us if not all have in our hearts.