What is the church? What defines it; and what constitutes it?
The word “church” can be defined in several different ways. It can mean the building in which Christian worship services take place; this is the etymological origin of the word (from German kirika, from Greek kyriakon meaning house (oika) of the Lord (kurios))
The word has also been used to translate the Greek word ekklesia which means “those who are called out” from the Greek ek (out) and kaleo (to call). This word was used in Greek to refer to public assemblies of people, possibly in the sense of calling them out of their houses and into the public forum to discuss civic or religious affairs and business. Thus, the word church can mean the assembly of Christians called together for worship.
This sense can also be spiritualized to mean not only the physical and local assembly of believers, but all those around the world who participate in those assemblies, wherever they might be, or some subsection thereof e.g. the Global Church, the Church of North America, the Church of Kansas City, the Nazarene Church, the Baptist Church etc. The Church Invisible consists of all those who belong to the Global Church, both on earth and in heaven, from all of history.
This sense can was further spiritualized in the Late Middle Ages as people started to realize that there was more to being a Christian than simply attending Mass. Being Christian, they began to articulate, is less about outward actions and more about an inner attitude and spirit (dare I say Spirit) which then results in those outward actions. Thus they began to speak of the “True Church” as the body of those believers who are not only Christian in name, but also in spirit.
All of these definitions have their legitimate place in English conversation, but to me, the one that is most helpful to discuss, and which is the least obvious in its constitution, is that last sense. When I use the word “church,” in my everyday conversation, that is normally the sense in which I use it.
This usage, unfortunately, is the least definite or concrete of any of the definitions of “church.” It’s easy to point to two buildings and say “That one is a church, that one is a roller rink.” It’s easy to see people who have gathered on a Sunday and say “all who are here are part of the Church, all who are not are not.” What is more difficult is to speak in any meaningful way about a body of people who are defined by their own inner convictions, motivations, desires, and failures. How do you know who is a Christian and who isn’t? How do you know who is a part of the “True Church” and who isn’t.
The problem, as I see it, is that we are trying to derive an objective measure for a subjective reality. We can’t know who is or is not a part of the “True Church.” There is no test or measure by which we can say “You’re in, you’re out.” We can have tests and measures and qualifications for membership in the local, and thus global, physical assembly; but we can’t define or objectively discern who meets subjective criteria, and thus is or is not a part of the “True Church.”
Ok, so why even talk about the “True Church” if we can’t take action on it? Well, I didn’t say that we couldn’t take action on it, I said that we couldn’t objectively tell who is or is not part of it. We need to talk and think about what it means to be a part of the True Church so that we can look at ourselves, each individually and think about our own participation in that Church.
So, then, what defines the “True Church.” It’s not defined by actions, sinful or righteous; it’s not defined by attendance or participation, that’s what defines the physical assembly. Participation in the True Church is defined solely by The Spirit.
When I define the True Church, I rely on the doctrine of the Trinity, and especially a sub-section of that doctrine which deals with the doctrine of the Perichoresis. Simply stated, perichoresis means mutual interpenetration. That is to say, it refers to a relationship in which two entities contain each other, or live within one another.
As pertains to the Trinity, Perichoresis means that the Father, Spirit, and Son contain and live within one another. John testifies to this when he records Jesus words “I am in the Father and the Father is in me.” (John 14:10-11). This perichoretic relationship is then echoed down through the reality which the Perichoretic God created, even to the church. John 15:9 and 12 record a simple formula which Jesus relays to His disciples: “As the Father has loved me, so have I loved you;” and “love one another as I have loved you.” The community of Christians is to relate to one another in the same (or a similar) way in which God relates to Himself. This paradigm is reflected in John 17:20-21 “"My prayer is not for them alone. I pray also for those who will believe in me through their message, that all of them may be one, Father, just as you are in me and I am in you. May they also be in us so that the world may believe that you have sent me” and has echoes in the Sermon on the Mount, in the Garden of Eden, and elsewhere in Scripture.
Here’s the theological nutshell: God established a relational paradigm for Creation; this paradigm is called Shalom, or The Kingdom of God, and is modeled by God Himself in the Perichoretic Trinity. God’s act of Creation was an opening up of that Trinity to include us in that perfect and perichoretic relationship of love and unity in which God perpetually exists (“As the Father has loved me, so have I loved you”); this reality is called Heaven. The Church, the True Church, consists of all those who accept the paradigm of Shalom and attempt to live in the world from the basis of God’s reality of relational wholeness (“Love one another as I have loved you.”). This is reflected in the Lord’s Prayer; the church consists of those who earnestly desire and sincerely pray “Thy will be done and Thy Kingdom come on earth as it is in heaven.” The objective and measurable external actions, called righteousness, are the fruit of this desire for, as I have said before, you can’t sincerely pray for God’s Kingdom if your hands are willingly seeking out and creating Hell; but they are not a measure of actual participation in God’s Kingdom (and therefore the church) as sanctification is a process, and even Christians may sin ( I John 2:1 “My dear children, I write this to you so that you will not sin. But if anybody does sin, we have one who speaks to the Father in our defense--Jesus Christ, the Righteous One.”)
So the church, the True Church is a result of God’s perichoretic movement; the church is the physical manifestation of an opening up of the Trinity to include creation, and specifically humans, into the heart of God. A Christian is an individual human who has accepted God’s invitation to be united with Him in perichoretic love; a Christian is one who allows God to live in him or her, and who accepts God’s invitation to live in Him. The church is, in some ways, a by-product of this movement (though God always intended the church to exist); for if I live in God, and God lives in you, then I live in you; and if, reciprocally, you live in God, and God lives in me, then you live in me. That is the structure of the church; how it’s built. The church is the extension of the Trinity into human reality through individual participation in the heart of God through the action of the Spirit, the grace of the Father, and the facilitating atoning act of Christ.
There are many more implications of this definition of the church than I can possibly go into in the short space afforded by a blog; but by reflecting on who we are in Christ, and therefore on who we are to each other, we can see the fruit of God’s Spirit begin to form in our communities. Know what the church is; know what makes us the church; know how you fit into the church; and consciously go and live out of that reality and into the world.
 http://etymonline.com/index.php?allowed_in_frame=0&search=church&searchmode=none Etymonline - still cool.
 This seems to be a common problem, at least in our society: confusing and mixing the objective and the subjective; and trying to derive the one from the other. It’s not possible to derive the objective from the subjective, or vice-versa, without interpretation
 Sounds kind of gross, doesn’t it?