I recently came across a quote from a professor of mine from Bethel University. I think this greatly speaks to the manner in which believers are to be giving themselves over to the kingdom of Christ, more so than the kingdom of man.
The holiness of the kingdom of God must be preserved. If Jesus refused to acknowledge and fight for Israel as God’s favored nation–even though it was the one nation in history that actually held this status at one time–how much more must his followers refuse to acknowledge and fight for America as God’s favored nation? To say it another way, if Jesus was committed solely to establishing a kingdom that had no intrinsic nationalistic or ethnic allegiances–not even with Israel–how much more should his followers be committed to expanding this unique, nonnationalistic kingdom?
– Greg Boyd, “The Myth of a Christian Nation” (2005, pg 153)