Throughout history to this very day, people are a mixture.  From the disciples, to the reformers, to us, people are a mixture of good things and bad things.  However, when we are saved God gives us His own Spirit to change the mixture.  He came to change us into the likeness of Jesus until we are no longer a mixture, but representatives of the Son in thought, word and behavior.  Our role is to allow and yield to His work inside of us - to respond to Him, refusing to allow anything to separate us from God or one another.  History shows us what happens when we don't do this. Division, hate and murder are results.  God is inviting us to be entirely changed, transformed, remaining unified and loving toward one another.