Since Israel has its fulfillment and continuation in Christ as a spiritual nation (the Church), the Kingdom of Christ also has to be spiritual. This is exactly what Paul taught:
Colossians 1:13 — 3 He has delivered us from the domain of darkness and transferred us to the kingdom of his beloved Son,
Christ’s kingdom is both spiritual and is now, in the form of His Church, which continues into the Eternal Kingdom of the “new heaven and new earth” (Rev 21:1-2).
This is why we know that there will not be and cannot be an earthly millennial kingdom, as Premillennialism teaches.