James 4:7-8 (NLT)
So humble yourselves before God. Resist the devil, and he will flee from you.  Come close to God, and God will come close to you. Wash your hands, you sinners; purify your hearts, for your loyalty is divided between God and the world.
- These passages remind me of Paul's admonitions to differentiate between being in the world, but not of the world. Our identity must be found in God alone.
I think there is a danger that we might take a wrong meaning here if not careful. Jesus himself is referred to as a friend of sinners (where is that?). So this warning by James should not be read in a way that makes us aloof and uncaring to our friends and neighbors.
In fact, if our identity is in Christ people should generally find something attractive about us. Something welcoming that says, "You are beloved, and significant to God and therefore to me."