Reading Ephesians 5 with Steve on Wednesday. I often find myself cruising through these back-end sections of Paul's epistles as if they're some after thought sticky-taped on. No doubt I'm governed by some misguided approach where I tell myself I'm in need for some 'real theology' not just some 'do this and don't do that'.
Of course that's all rubbish - everything Paul says is completely rooted in what God has done for his people. We're called to be 'imitators of God as beloved children' (5v1). Paul's not whacking Christians over the head with a load of 'to-do' lists, rather he's getting right into the heart of the relationship between Christian theology and Christian living.
The call to imitate God is not some wishful thinking on Paul's behalf, but rather its based on the wonderful reality that we are now God's beloved children, and children imitate their parents. This pattern pops up again and again in the back end of Ephesians - reason for action is everything, and for Paul the reason is knowing who we are. In v3 our identity as 'saints' means certain stuff isn't even to be named among us. In v4 it isn't that filthiness and crude chat is bad that should stop us from doing it, but that it's 'out of place'. Again, in v7-8, 'do not associate with them; for one time you were darkness, but now you are light in the Lord. Walk as children of light...'.
Christian ethics, that is how you live as a believer in Jesus, is always worked out and motivated by taking note of who you are. It's what fits. Of course if there's no knowledge, if there's no awareness of who we are, then we're either gonna forget and worse head elsewhere for our sense of identity, or we're gonna drift into a stuffy moralism that has lost sight of reasons and truth and thinks of Christianity as actions alone.
That's why simply remembering my identity, as a child of God, a joint of Christ's body, a member of the household of God, is such a precious and cruical thing to do each day. It rams home the importance of a book like Ephesians in stopping us in our tracks and giving us a reality check. This is reality.