How do we know the millennial reign of Christ is spiritual?

The understanding of the millennial reign of Christ as spiritual rather than carnal is supported by several scriptural references. For instance, in John 18:36, Jesus clearly states, 'My kingdom is not of this world.' This declaration highlights that His reign does not conform to earthly expectations or structures, but is realized internally among believers. Additionally, in Luke 17:20-21, Jesus explains that the Kingdom of God does not come with observation; it is 'within you.' This reinforces the understanding that the millennial reign is characterized by the presence of Christ among His people rather than a physical dominion over earthly nations.

Furthermore, the concept of two kingdoms and two purposes, as proposed by premillennialism, dilutes the sufficiency of Christ's redemptive work. In reality, all believers, irrespective of their ethnic backgrounds, are incorporated into one body of Christ (Ephesians 2:14-16). This singular focus on spiritual restoration stands in contrast to a dualistic interpretation of God's purpose, affirming that His glory is manifested in saving unworthy sinners from all backgrounds, not just a select group.