Romans 16:7 Salute Andronicus and Junia, my kinsmen, and my fellowprisoners, who are of note among the apostles, who also were in Christ before me.
Paul used the phrase "in Christ" frequently in his writings. It is a “marker of close association within a limit.”BDAG So not everyone is “in,” and there are requirements to get “in.”
The requirement for entrance into this "close association" is personal faith in the Gospel work of Jesus Christ. Paul clearly spelled this out in Romans 3:19-31.
A person who is “in Christ” enjoys the benefits of a permanent relationship with the King of Kings and Lord of Lords. These benefits include: His personal care and concern, His love, eternal life, and the perpetual presence of His Spirit.
Adrian Rogers said, “The key to living a victorious Christian life is to discover who you are in Christ. Many Christians have never discovered this. They remind me of the man who had an identity problem and an energy crisis at the same time. He didn’t know who he was and he was too tired to find out.”
For believers, “in Christ” is not where we are, but who we are. God doesn’t work from the outside in, He works from the inside out. He doesn’t modify our behavior to change us; He changes us, then everything about who we are is affected.
You’re never going to purify the water by painting the pump. That’s legalism and it’s a dead end to discovering who you are in Christ.
Search God’s Word for the phrase, “in Christ.” As you find phrases that apply to your life, write those down. Begin with phrases such as “no condemnation” now that you are “in Christ.” Romans 8:1
If you are not “in Christ,” but are curious, begin by understanding the gospel. I’ll be glad to help you, just write.