In Ephesians 5:6-8, Christian ethics is not based on God’s commandments, but rather on our new identity in God. We are not to deceive or disobey. Why not? “For you were once darkness, but now you are light in the Lord. Live as children of light.” There is an “ought” here: You ought not to deceive or disobey. Instead, you ought to live as a child of the light. This “ought” is based on the “is” of your new identity: Now you are light in the Lord. If we want to find out what we “ought” to do (and not do), we need to pay attention to the “is” of our identity in Christ.