What is the opposite of peace?
I think most people would answer “it depends on what kind of peace you mean.” In other words, if you mean peace between adversaries, then the opposite is “hostility.” If, however, you mean peace in terms of calmness and serenity, then the opposite is “anxiety.”
I would argue there’s no difference.
Peace is peace, whether it’s describing the absence of hostility or the calmness of a person content in Christ. Peace is peace. When we have a feud with someone else and that feud is settled and ended, we say “we are at peace.” What does that mean? It means there is now calmness and serenity between those two who were once at war.
What is anxiety?
It’s is the feeling we get when we are at war with our own thoughts. It’s how we feel when we take the circumstances of the world, sharpen them into fine points through constant contemplation, and repeatedly stab ourselves with them with worry and fretting.
What we need when we’re at war with an enemy is peace. What we need when we’re at war with our thoughts is the same thing. We need peace. How do we attain peace with an enemy? We go to them, confess our faults to them, and ask forgiveness (Luke 17:3). How do we attain peace with ourselves? That’s much more challenging, though the Bible is just as clear about what to do: Pray and be content (Philippians 4:6, 11).
Why is it so much easier to make peace with someone else than it is with myself?
Maybe it’s because I live with myself. I live inside my own head. My enemy whom I reconciled with, I may only see a few times a day, a month, or a year. But I am constantly thinking, so it is a constant struggle to fight against anxiety.
I don’t think anxiety is a war the Christian ever permanently wins (in this life); I think it’s a daily fight that we simply endure and survive with the help of Jesus. But, with the help of Jesus, we win the daily battles fought within our minds.