Recently our weekday Bible study held the first class on the topic of union with Christ. We listened to a video lecture by Sinclair Ferguson, a Scottish theologian who is known in Reformed circles for his writing and teaching. He asked this question: How do you describe your faith? Most of us would answer by giving our denomination — Lutheran, Baptist, Methodist, etc.– or maybe we would just say “Christian.”
In the early church, few believers would have responded this way. At that time Christian was a derogatory term. Instead, they might have called themselves “followers of the Way” or as Paul describes himself, “a man in Christ.” (2 Corinthians 12:2). Paul actually uses this phrase, or others similar to it (in the Lord, or in Him) more than 80 times in his letters. It’s obvious that being “in Christ” cannot be separated from the rest of Church doctrine — it is, in fact, the background of everything else Paul has to say.

We are in Christ, and Christ is in us. This is called the mystical union between Christ and every believer. Simply put, it’s a way of understanding and speaking about how we share in the life and death of Christ. All the spiritual blessings we receive are due to our union with Him.
For more about faith see: