As I read through a quick summary of African slavery by Sean Stilwell, the clear demarcation between the many-times terribly abstract slavery and freedom is the issue of belonging. In all forms of African slavery, freedom meant a kind of substantial belonging to a larger social network. Slaves as outsiders had no kin networks and thus were completely powerless and totally beholden to their masters. Some forms of African slavery ameliorated this as slaves both were junior (the lowest) kin-members and also had paths for adoption into the kin-network.
However, the key component is that African slavery made the distinction the way it did. Slaves from further away were coveted more than those from nearer regions. Why? Because the further away from a slave's homeland, the less chance there would be claims of kinship. When one was utterly disconnected from kin-networks, he had no recourse to justice. Anyone from anywhere could subject him to violence.
In the modern Western world families do not function in the same capacity (with the exceptions of mafia). Families do not imply real social power, if any at all . The most one gets nowadays is that so-and-so knows your father and is willing to give you a job on account of it. But families are no longer social bodies that can make any claims for constituent members in the larger political world.
In Hannah Arendt's account of Totalitarianism, she describes the condition of the Modern, post-World War 1, world where belonging to a nation-state was the new standard for belonging. What the Nazis, and other Totalitarians did, was institute programs of making undesirables stateless. Nazi propaganda reinforced the stereo-type of the Wandering Jew, begging and scraping like a rodent, while, simultaneously, divesting Jews of their place within the German (and for the Nazis, this was the world) state, This led to a kind of fulfilling of the stereotype, only justifying the 'Final Solution' the propaganda demanded: they must be exterminated like bed bugs.
As Arendt has argued, we still live in a world where belonging to a state is what guarantees one a certain kind of just complaint. If you are stateless, violence against you is guaranteed as there will be no one to protect your or seek vengeance. While the UN was trying to produce a meta-state solution, it is largely toothless and used a legitimizing tool for its leading members (as the League of Nations before it). The Roma (gypsies) still suffer as they are stateless. They are abused by angry nationals who take out their frustrations upon immigrants who are known for theft and privacy.
In both of these examples, the family and the state are the enforcers or advocates for justice for its members. Without them, even the guilt, shame, or historical memory will be erased. For example, during the Armenian Genocide, the Turks were able to commit "legal" purges because the Armenians had no legitimate advocate, and thus they were easy prey to conquerors. Thus the Armenian Genocide is largely swept away, besides some lobbyist groups that make a little noise that is mostly ignored. Yet with that weak voice, the Armenian nation (both in the nation-state) still speaks with a voice for the dead, and that is because it became the social-network necessary to do so.
The Apostles speak of the Church, that is the people adhering to Christ as Lord, in terms of both state (polis), family, but even other networks (e.g. koinonia was a kind of guild/professional-network/club). My contention is that the power of these metaphors is not in sentimentality or political strength, but in their abilities to create social networks.
For many early Christians, if one was abandoned by kin or by state for their Christian allegiance, or if they were already a marginalized member (e.g. slaves, women, non-Romans), they had no social network to find support in. The problem St. Paul saw in people dragging each other off to law-court was that they were abandoning their role and responsibility to take care of themselves within a new social network, one that operated by a different set of laws than the rest of the present age.
However, before I go further, the hope is not to build a rival family or a rival state. The Imperial Papacies of later years would confuse the Apostolic witness and commit all sorts of crimes, many in the best intention. For Thomas to say it is better to burn a twice-turned heretic for the greater good is both a logically consistent and yet wicked thing.
But it is only wicked if this whole model of an Imperial Church is wrong headed. The Church is not supposed to be a family or a state, but an analogy of those things. The purpose is to form an alternate society. But this society does not (and should not) separate from the ruling social network. Distinction does not imply opposition, nor does distinction require one for one replications. It's largely for this reason that some early Christian apologists described the Christians as a new race made out of peoples from all nations. It has nothing to do with bloodline.
Despite the pastoral uses of this doctrine in Sonship model, the concept of adoption is the logic behind claims to being a new social-network. We belong to one another because we have now become children of God the Father, the Creator and Judge of all, through Jesus Christ in the work of the Holy Spirit. The Son by Nature has made us all sons by grace.
Now, I believe the old dictum that the church catholic(universal) can be found in the local church. That is to say, we need not desire after some false universalism (like the claims of Rome) in order to see the universal Church in our own particular congregations. As an aside, I'm arguing for networks, that extend beyond denominational lines, but don't equate to congregational models. One can still maintain a kind of episcopacy even within this.
Thus, the local church can be this social network that labors on behalf of its constituents. Of course most church-communities in the United States are ignorant, and quite a few are actually committed to a cult of Americana and have departed from the Lord. But the ignorance is most pronounced amongst white Protestants. As chief beneficiaries of the super-state social-network, we suckle the tit and ignorantly pontificate (I'm not excluded). We don't see why other societies exist within the greater and seem at odds, or weary of it. It doesn't make sense to most why some black Americans would fear the police as much, if not more, than a local gang, and have alternative means to problem solving than simply calling 911.
This post could go on for much longer, but it's already gotten much to long. But I will add one more fact:
While the church-community's members will be a social matrix for one another, the Church of Christ is a social body that exists for the sake of others. This is not a call to heroism or a kind of savior complex. Rather, it's willing to come alongside the voiceless for the purposes of allowing the 'outsider' a place of protection and advocacy. It's being willing to be hated for being found among the most worthless in society. It's among the 'outsider' that Christ may in fact be found (Matt. 25). Again, this is not a liberal crusader mentality. It's not trying to save anyone, absorb them, or turn them into a cause. Rather, it's the willingness to simply be around those whose social-status will mar your reputation. You'll get no credit for it.
An example might be how Richard Wurmbrand describes the treatment of the former prison warden. After a Romanian regime change, the prison-warden found himself out of favor with the new Party elite and wound up being jailed. In his cell, most prisoners remembered his cruelty and viciousness and wanted to beat him to death. That'd be fitting. But this now social-outcast, this 'outsider', was protected by some Christians in the jail. They were willing to forgive him and seek his transformation away from such a life of violence. These Christians almost found themselves beat to death for willing to advocate on behalf of such a wicked enemy.
This is an extreme example, but loving your enemies tends to be the most thoroughly harrowing example of what it means to advocate for the outsider.
These are the ways the Church, found in all church-communities who still cling to Christ, uphold the Apostolic metaphors. It's this way that we can corporately love one-another. It's the way Christians are faithful to the command to be in the world, but not of it. This is part of the work of the gospel.