In this country there is a myth that is being perpetuated by history revisionism (like Focus on the Family's Truth Project) that removes this balance outright. They think America is the Kingdom, and we're supposed to be (as a nation-state) the "City on a hill." The editor of the recent American Patriot's Bible said we send out American Christian Missionaries around the world "so that other nations may know the God who has so richly blessed us."
They don't see a balance. The Catholics have their saints in martyrs, and these civic-religionists have their saints in soldiers and Presidents.
Most mainstream denominations would find a balance through Luther's "two kingdoms." Of course many people give this lip service, but actually promote something else (much like they do with just war doctrine).
And then there are others who see the Church enacting the new Kingdom now as a living witness to the coming Kingdom. This is much how the early Ante Nicene church lived. They did not participate in civic functions (preventing believers from entering magisterial positions), they did not participate in civic duties (like allegiance to the Caesar). They were called "atheists" for this.
They lived as strangers in this world, citizens of a "new country" with only one Lord, the Christ Jesus.
They looked to Abraham who was promised a land but did not ever posses it. They viewed the Church as such, striving for this land in faith. (Acts 7, Philippians 3, Hebrews 11)
1 Peter is full of references to the Church living as "aliens and strangers in the world." We're to be peculiar.
Israel in exile is another example the leaders pointed to. They were in pagan lands and would not live as they lived, and remained separate. But they sought peace in this land (Jeremiah 29:7), they didn't just help those in need within the fellowship but also without.
But one passage I look at and struggle with on finding my own balance is 2 Corinthians 6
"We put no stumbling block in anyone's path, so that our ministry will not be discredited." (v.3) But the world sees so many Christians hunger for power, they don't see us as genuine. We sell out our beliefs to gain political power.
This American church is hardly described as Paul goes on through vs. 4-10. If we don't fight back "in great endurance; in troubles, hardships and distresses; in beatings, imprisonments and riots" it would be uncommon, when we should respond "in purity, understanding, patience and kindness; in the Holy Spirit and in sincere love; in truthful speech and in the power of God." And there are very few fellowships who are "poor, yet making many rich; having nothing, and yet possessing everything."
And then vs. 14-18 is an indictment on our involvement in the democratic system. "Do not be yoked together with unbelievers. For what do righteousness and wickedness have in common? Or what fellowship can light have with darkness? What harmony is there between Christ and Belial? What does a believer have in common with an unbeliever?"
This is not in the context of relationships between men and women, but in the Church and the world. Can a Christian and non-Christian co-operate a business and not feel these words? Can a believer and unbeliever have commonality in the voting booth?
"What agreement is there between the temple of God and idols?" Does this not speak to us who have Democracy itself as an idol? We swear allegiance to a man-made flag, swear oaths to defend a man-made document, and affirm the rulings of elected and appointed officials. Are these not idols? What are these graven images in our nation's Capital? These stone men in temples of granite and marble.
Therefore come out from them
and be separate, says the Lord.
Touch no unclean thing,
and I will receive you.
So I struggle with this. The Church, not of this world, seems so much a part of it.