"Why are you angry, and why has your face fallen? 

There was a cause for Satan to get in to Cain. It was envy. But what was it that made him get to Judas? If you do well, will you not be accepted? And if you do not do well, sin is crouching at the door. Its desire is contrary to you, but you must rule over it. What sin is crouching at your door?