We once lived according to the old self, which focused on self.  However, thanks to Jesus Christ, when we surrendered to Jesus, we were given a new self that is capable of saying no to sin and obeying God.  But we know that just because we are freed from the power of the old self, it doesn’t mean we have fully overcome its temptations. Because we are God’s children we are to put on the new self with its true righteousness and holiness – we are to be different.