Thankfully most people aren't into Slayer but there are so many people that are against Christ (or they're not FOR him, which amounts to the same thing actually) and today John speaks about the difference between those who are for and those who are against Jesus...
There's been a lot of talk about 'antichrists' over the years. At various times throughout history, people in the church have asserted that they know who it is. They've been waiting for an incredibly evil figurehead to pin it on. People used to say it was Napoleon, Hitler, Stalin, MacDonald's, Waitrose, the Pope, and the list goes on!
John doesn't tell us to look out for one evil figure. He's a lot more real than that. John basically says that anyone who's not for Jesus is against him. They prove it by their actions because they have no time for him in their lives. They go off on their own way and live life exactly as they want to, with themselves in the driving seat and calling all the shots.
The stunning verse in the middle of this bit is where John tells us who the real liars are (strong words). He says the real liars are the ones who flatly deny that Jesus is the Messiah (or chosen one of God). Blimey!
The thing is, I think God has made it so obvious he loves us and he's spoken with so much clarity to show us that he's real and loves us but people still fail to recognise it. Creation itself, conscience, ethics, guilt, compassion, creativity, love, anger at death, logic. All these are clear reasons we have that God is real. Then we have historical evidence about Jesus. The evidence for his existence is unquestionable and the evidence for his resurrection is overwhelmingly compelling. The empty tomb, the 500 witness, the eye-witness accounts in the gospels (written within living memory of Jesus), the martyrs that died for the story of what happened, the dead body that was never found. It's very obvious that Jesus was and is someone uniquely special that came to save us. Maybe he really was and is the only Son of God who came to save us from our sin - but tragically most people ignore it or hate it so much that they agree with Slayer!
What about you? What do you say about Jesus? Have you explored the evidence or just pushed it to the back of your mind or gone along with what most people believe? The dangerous thing about following common sense is that it's becoming increasingly less common and you might end up missing out on the one truth that could save your life.
Or maybe you've made your mind up already and you're a Christian living for Jesus. John's words are, 'remain in him' (v27). Stay put. Don't stop thinking but also don't forget the biggest truth that you've been shown. Live in it and share it with others who need to know but do so with an open and thinking mind and in a way that shows people what Jesus is like rather than being arrogant and clouding people's vision of who Jesus really is.