Satan disguises himself as an angel of light; So it is no wonder that his servants also disguise themselves as servants of righteousness.
See 2 Corinthian 11:14-15
Something To Think About:
Satan's favorite strategy is to make sin look desirable and good and to convince us that what is really true is false. If Satan can make evil look good and good look evil, then you are giving in to temptation which appears right instead of wrong.