A friend of mine once gave me an analogy about purity.
It's like poop. :-)
Imagine a glass of pristine pure water. If I dropped a piece of poop in it, would it still be pure? Would you still drink it? Of course not, unless you were looking to get sick. What if we just made it a little piece of poop. Is that better? No.
We live in a world that is corrupted by evil. It lacks purity. Does it matter whether we are exposed to a little impurity or a lot? Like the glass of water, a little poop goes a long way. As long as we remain in the waters of our world, we will become soaked in our own filth. Does this mean that culture is all bad? Of course not, there is plenty of good water there in with the poop.
So where do we turn to make us pure?
Unfortunately, there is nothing in an impure world that can make us pure. We must somehow separate from the world in order to find purity again. Jesus asks us to remain in the world but abide in Him. He acts as a second skin that both protects us from impurity and purifies us.
When we abide in Christ it is as if we are pure bubbles floating in the water. God is filling our space with purity, and with time, our bubbles grow and merge, becoming communities that are pure, refreshing, and astounding.
Jesus is creating sparkling water out of poop water. Where would you like to swim?