In two recent posts here and here I emphasized how the devil is actively trying to deceive us and trick us. I've noticed that some Christians don't seem to think about this very realistically. They either seem to think that they're on the sidelines watching a match between the devil and God, in which the outcome is important to us but which doesn't really affect our daily lives, or they think of the devil as an abstract concept of evil instead of a living being that could threaten any one of us personally. Perhaps you're the type of Christian who doesn't give the devil much thought on an average day. I want to change your mind.
The opposition is real and direct. Paul declares that he was prevented from coming to see a church in one city because “Satan hindered us.” (1 Thes. 2:18). He warns believers to put on the armor of God so they can withstand the "schemes of the devil." (Eph. 6:11). Paul also warns that the devil is trying to catch believers and unbelievers alike in a snare. (1 Tim. 3:7; 2 Tim. 2:26). Peter says the devil is prowling around "like a roaring lion" to devour people. (1 Peter 5:8). And James tells us to personally resist the devil. (James 4:7). Andrew's sermon has many more helpful examples and is well worth listening to or reading.