Al Imam ibn ul-Qayyim al-Jawziyyah mentions in his tremendous book "al-Jawaab ul-Kaafy li man sa`ala 'an id-dawaa` ish-Shaafi" also called "ad-Daa`u wad-dawaa`", "...and also in 'al-Hilya' [is a report] that ibn 'Abbaas said, 'Oh sinner, don't feel safe from the evil consequence of it (sin). And that which comes along with sin is greater (in evil) than the sin: The minute amount of shyness that you have from the one on your right and the one on your left while your committing sin is greater (in evil) than the sin; and your laughing while you don't know what Allah will do with you is greater (in evil) than the sin; and your happiness with sin when you commit it is greater (in evil) than the sin; and your sadness over sin when it ( the chance to commit sin) passes you is greater (in evil) than the sin; and your fear of the wind when it moves the door which veils you while you're committing sin, and your heart isn't disturbed (by the fact) that Allah sees you is greater (in evil) than the sin. Beware! Do you know what the sin of Ayoob was for which Allah tested him in his body with severe sickness and by the depletion of his wealth ? A poor man sought his help against an oprressor that he might repel the opressor. So, he (Ayoob) didn't help him, nor did he prohibit the oppressor from his oprresion so Allah tested him."