Pastor Greg Laurie warns about the tactics and strategies of Satan, the accuser of the brethren, and how he works to deceive and condemn believers. He explains how the devil is like a serpent, hard to read and unpredictable, and how he uses fear, kindness, and vulnerability to tempt people into sin. Pastor Greg also emphasizes the importance of knowing God's protection and power, and how believers can resist the devil and live a life of faith and action.