What It Means to Be in Christ
One of the main themes in Ephesians is Paul's continual emphasis on our union with Christ. If you don't believe me, just sit down with your Bible and a pencil and read Ephesians 1-3 and underline every time Paul says something like 'in Christ' or 'in Him' or the like. You will soon be overwhelmed to organize all of it in a coherent way. As those who are in Christ, we need to understand that all of our existence is in Christ. And here is a quote that helps illustrate the immensity of our new identity in Christ.
Most of us have wondered, at one time or another, if we were switched at birth. “Are those really my parents?” Now, imagine your parents are mean and critical, that you have always been a disappointment to them and they to you. But then, one day, you find a dusty trunk in the attic. You quietly pick the lock and open the trunk and discover papers that prove you had, in fact, been abducted as a baby. These aren’t your parents after all— why, they’re criminals!
You discover that your real mom was a painter at the Sorbonne in Paris and your real dad was a Nobel Prize– winning scientist and a professional baseball player. And you say to yourself, “Of course, this explains everything! I am extraordinary! I knew it all along.” You also read that they are fabulously wealthy and have a lavish inheritance waiting for you.
It’s a fantastic story, but you get it. Such a discovery would cause you to reinterpret everything about your life: where you came from, your true identity, your capacities and capabilities, the resources available to you, your future, and your destiny. After that day, your life would never be the same. You would come down from that attic with new eyes for everything and everyone. Your whole life would feel new, changed, and invigorated.
But here’s the thing— it had always been true. It was the truth underlying your life even before you discovered it. It was rooted in history, and you had the DNA to prove it. It was true while it was hidden from your sight. But it didn’t change your life until your eyes were opened to it.
O dear child of God, do you know who you are? Do you know that God chose you in Christ before the foundations of the world? He told His beloved Son, 'Son, bring her to me; O Son, bring him to me. O my beloved Son, go to bring them to me.' In Christ, God delights in you! Have you come to understand what theologians have called union with Christ? Dear Christian, do you understand your identity in Christ? Do you know who you're? Let this union drive you to communion (read devotions, or quiet time, or pray) with God in and through Christ.
 Rankin Wilbourne, Union with Christ: The Way to Know and Enjoy God (Colorado Springs, CO; David C. Cook, 2016), Kindle Locations 154-166.