The command "Be ye prfect" is not idealistic gas. Nor is it a command to do the impossible. He said (in the Bible) that we were "gods" and he is going to make good his words. He will make us into a god or goddess, a dazzling, radiant, immortal creature...a bright stainless mirror which reflects back to God perfectly.
Source: Mere Christianity
Contributed by: XjoshX