“For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh.” This is a profound mystery–but I am talking about Christ and the church. (Ephesians 5:31-32 NIV)
At creation God did not create Eve from the ground like He did Adam. He created Eve from the rib of Adam. Adam and Eve came from one body. In marriage, two become one again. In our verse today, Paul is saying that the church is to be one in Christ. The two will become one. As individuals, we also become one with Christ. The more time you spend in prayer and studying the Bible the more you change. The more time you spend with Christ the more you become like Him.
And we all, who with unveiled faces contemplate the Lord’s glory, are being transformed into his image with ever-increasing glory, which comes from the Lord, who is the Spirit. (2 Corinthians 3:18 NIV)