What does the Bible say about our union with Christ?

In John 15, Jesus describes Himself as the true vine and believers as the branches. This metaphor illustrates the essential union between Christ and His church, emphasizing that spiritual life and productivity stem exclusively from this connection. Just as a branch cannot produce fruit without being connected to the vine, Christians cannot bear spiritual fruit apart from their union with Christ. This union is a direct result of Christ's incarnation, where He took on human flesh, ultimately allowing us to be spiritually joined to Him, becoming His body with Him as the head. Therefore, our relationship with Christ is fundamental to our spiritual vitality.