The concept of a "church" in the Writings is both complex and beautifully organic, linked with teachings on the nature of the Lord and the resulting nature of mankind.

The Writings say that the Lord, in His essence - His actual substance - is perfect, infinite love, a love that powered creation, that is the ultimate source of reality, and that sustains reality constantly. That love is expressed in form as perfect, infinite wisdom, which gave form to creation and gives form to reality.

Deep stuff! You can read more about that elsewhere, but what matters here is that all of creation, from the smallest elements to the whole of the universe, reflects that same structure. It's present in nature itself, powered by the heat (love) and light (wisdom) of the sun. It's present in the essential forms of life, with plants (which are rooted; which change little; which are unfeeling; which are powered by light) representing elements of wisdom and animals (warm, feeling, mobile, ever-changing, powered by heat) representing forms of love. It's present in the near-universal division into male (wisdom) and female (love) aspects of plants and animals alike.

That structure is also in each of us. In common language we might call these our hearts and our minds - what we want and what we think. The Writings commonly talk of them as good (love; what we want in our hearts) and truth (wisdom; what we know in our minds) or as will (heart) and understanding (mind). Not only do these elements define us, they are also key to our spiritual fates. We can use them to accept the Lord's love, come into the good of life and ultimately go to heaven. We can also use them to reject the Lord's love and trot off to hell.

And there are further layers. The Writings say that all human societies are in human form, with functions analogous to the human body. This is true from small groups like families to large companies to entire nations and ultimately to both the entire human race in this world and the entirety of heaven in the next.

Among the most important human societies are, naturally, churches. Since the concept of a "church" is based on the human form, though, churches as referred to in the Writings can take many forms. At one end of the scale, any one person who has true ideas of right and wrong and lives by them is a church himself or herself. At the other end of the scale, all those in the whole world who believe in love of the neighbor – and act from that belief – collectively make up one church.

Many other varieties lie between those two extremes, but most references to "church" in the Writings mean the community of those who have the Word, know the Lord, and follow His commandments. These people have access to the best possible truth and deepest possible understanding about the nature of the Lord and what He wants from us.

Such a church plays a vital role: The Lord works through it to get ideas about being good into people's minds and the desire to be good into the inner recesses of their hearts, reaching far beyond that church itself to touch everyone in the world. In fact, the Writings say there is in essence a marriage between the Lord and the church, with the church in the role of the bride and wife, producing true ideas and good desires the way a wife produces children.

To protect this function, the Lord has made sure that throughout history (and a good bit of prehistory) there has always been a church filling this role.

The first of these was the Most Ancient Church, represented by Adam; it was inspired by love of the Lord. The second was the Ancient Church, represented by Noah; it was inspired by love of the neighbor and knowledge of the Lord. The third was the Israelitish Church, which had no interior love of good but preserved ideas of the Lord. The fourth was the primitive Christian church, which had a new, more direct understanding based on the Lord's teachings. The fifth, according to the Writings, is to be based on the deeper understanding offered through the Writings and their explanations of the Bible.

There is much more that could be said, but we'll just emphasize one other point:

We as individuals are who we are based on what we love, not what we know. We will go to heaven or to hell based on what we love, not what we know. Knowing, thinking and seeking truth are important things, but their purpose is to shape, guide and serve our loves; love is ultimately what matters. The Writings make it abundantly and repeatedly clear that it is the same with churches: They are ultimately based on love, not knowledge, on their determination to serve the neighbor, not their external forms of worship. And if churches share that common purpose of serving the neighbor then they are in essence one, with doctrinal variations being of little consequence.

(References: Apocalypse Revealed 533; Arcana Coelestia 407, 768, 1799 [3-4], 2048, 2853 [2-3], 2910, 2982, 3310, 3773, 3963 [2], 4292, 4672, 4723, 5826 [2-3], 6637, 6648, 8152, 9256 [4-5], 9276 [2]; Conjugial Love 116; Heaven and Hell 57; The Word 8; The Doctrine of the New Jerusalem Regarding the Sacred Scripture 99, 104)

57. We can say the same of the church as we have of heaven, since the church is the Lord's heaven on earth. It also has many components, and yet each is called a church and is a church to the extent that the qualities of love and faith rule within it. In it, the Lord forms a single whole out of the varied elements, and therefore makes a single church out of many churches. ¹

Much the same can be said of the individual member of the church as has been said about the church in general, namely that the church is within and not outside, and that anyone is a church in whom the Lord is present in the qualities of love and faith. ²

Much the same can be said of the individual who has the church within as has been said about the angel who has heaven within, that such an individual is a church in least form as the angel is a heaven in least form. Even more, we can say that the individual who has the church within is a heaven just as much as an angel is, for we have been created to enter heaven and become angels. So anyone who has the quality of goodness from the Lord is an angel-person. ³

It is worth noting what we have in common with angels and what we possess that they lack. We have in common with angels the fact that our deeper levels are formed in the image of heaven and that we also become images of heaven to the extent that we participate in the qualities of love and faith. What we have that angels lack is that our more outward levels are formed in the image of this world; and that to the extent that we are engaged in what is good, the world within us is subordinated to heaven and serves it; ⁴ and that then the Lord is present with us on both levels as he is in his heaven. He is actually present on both levels in his divine order, for God is order. ⁵

Footnotes:

4839. 'And what he had done was evil in the eyes of Jehovah' means that it was contrary to Divine order. This is clear from the meaning of 'evil in the eyes of Jehovah', or evil contrary to Him, as that which is contrary to the order originating in Him. This is evident both from what Onan actually did and from what was laid down regarding a husband's brother - the sister-in-law was required to remove the shoe from his foot and to spit in his face; and his name in Israel was to be called, The house of him that has his shoe taken off, Deuteronomy 25:8-10. These actions meant that he was devoid of good, external and internal; and those who are devoid of that good and are governed by evil are contrary to Divine order. All evil that wells up or flows from evil present interiorly - that is, which, like Onan's, is intentional or has an evil end in view - is contrary to Divine order. But that which does not well up or flow from evil present interiorly - that is, which is unintentional or has no evil end in view - may sometimes look like evil but is not in fact this if the end in view is not an evil one; for it is the end that determines the true nature of every action. The end holds a person's life within it; that is to say, what a person loves and consequently thinks he has as his end in view. The life of his soul is nothing else.

[2] Everyone realizes that evil is contrary to Divine order and good is in keeping with it. Divine Order is the Lord Himself in heaven, for Divine Good and Truth received from Him constitute order. They do this so completely that they are order, Divine Good being the essential element of it and Divine Truth the form given to this. When represented in a visible shape Divine order is seen as a Human Being, for the Lord alone who is the producer of it is Man, 49, 288, 477, 565, 1871, 1894, 3638, 3639. And insofar as angels, spirits, and men are recipients of Him, that is, insofar as good and accompanying truth are present in them, thus insofar as His Divine order is present there, they are human beings. This is the reason why the whole of heaven represents one complete human being, called the Grand Man, and every single thing in the human being corresponds to it, as has been shown at the ends of chapters. It also explains why all the angels in heaven are seen in a human shape; but evil spirits on the other hand are deluded into seeing one another as human beings, whereas in the light of heaven they look like monsters, ever more dreadful and horrid, depending on the evil which governs them, 4533. The reason for this is that evil itself is contrary to order and so contrary to the human form. For as has been stated, when represented in a visible form, Divine order looks like a human being.