One Spirit: The Believer's Mystical Union with Christ

He that is joined unto the Lord is one spirit (1 Corinthians 6:17). The apostle Paul, when dissuading from impurity, eschewed mere physical or social arguments. Instead, he appealed to Christianity's loftiest principles—the bond between believers and their Lord.

This union operates through three dimensions: First, through faith (pistis)—Christians receive Christ Himself to dwell in their hearts, having not seen Him. Second, through love (agape)—joined as bride to bridegroom in spiritual affection, stronger than death. Third, through affinity—drawn as sinners to the Saviour, remaining as congenial friends in character and aim.

The consequent unity manifests three marks: Believers stand in subjection to the Father, whose will reigns supreme. They share one love for all holiness and moral virtue, their sympathy rooted in principles that dignify the moral life. They inhabit bonds of immortal fellowship—"that they may be with Me where I am" (John 17:24).

This mystical union produces practical proofs. The believer exhibits repugnance to all which repels Christ, rejecting the vices Paul addresses in context. More positively, the "one spirit" cultivates brotherly love, linking the mystical body of Christ in sympathetic, harmonious action.

The union itself operates at multiple levels: election from before the foundation of the world; covenant when Jesus became Head of His Church; the incarnation itself. Yet the vital, spiritual union occurs when one is born again—the foot baptized into the same Holy Spirit that anointed the head.