Here in England, we don't tend to fear much from the animal kingdom. We can wonder around at night and be more afraid of man than beast. We can walk through a forest and know that our ancestors killed pretty much everything that would seek to eat us. When we lay down at night, we know that our doors are locked, our walls are solid, and for me, personally, the toughest animal in my local area happens to be a beloved member of my family who sleeps in my bed. As such, we have let our guard down a lot.
Not so for Peter and his ilk. They lived in a difficult time when wild beasts were not unheard of. It was a difficult time in which even lions could roam the streets, and so most people would have their guard up.
When Peter warns us that Satan is like a roaring lion, looking for anyone he can devour, he wasn't playing around. He was telling us that this foe merits our attention. Satan is out there, and he can do some very nasty things to us. If he cannot prevent our salvation, he can certainly alter our lives, both spiritually and physically.
What would you do if you knew there was a chance of encountering a lion in your daily life? On your way to work, when you're out shopping, when you're walking your dog, if you knew you could encounter a lion at any point, you're probably not going to waltz around alone, unarmed, and buried in your phone. So what do you do knowing Satan is looking for any opportunity to devour you?
Don't treat your faith like a joke. Don't act like it doesn't matter. Don't assume saved = safe. Study your Bible, live out your faith, don't let your prayer life slack. There is safety in numbers, so find a Bible-based congregation, and if you can't find one, form one. Satan is looking for you, and he's angry. Don't let him catch you off guard.