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)

3310. 'A man of the field' means the good of life that has its origin in matters of doctrine. This is clear from the meaning of 'the field'. In the Word reference is made in many places to the earth (or the land), the ground, and the field. When used in a good sense 'the earth' means the Lord's kingdom in heaven and on earth, and so the Church, which is the Lord's kingdom on earth. 'The ground' is used in a similar though more limited sense, 566, 662, 1066-1068, 1262, 1413, 1733, 1850, 2117, 2118 (end), 2928; and the same things are also meant by 'the field', though in a more limited sense still, 368, 2971. And since the Church is not the Church by virtue of matters of doctrine except insofar as these have the good of life as the end in view, or what amounts to the same, unless matters of doctrine are joined to the good of life, 'the field' therefore means primarily the good of life. But in order that such good may be that of the Church, matters of doctrine from the Word which have been implanted within that good must be present. In the absence of matters of doctrine the good of life does indeed exist, but it is not as yet that of the Church, and so not as yet truly spiritual, except in the sense that it has the potentiality to become so, like the good of life as this exists with gentiles who do not possess the Word and therefore do not know the Lord.

[2] That 'the field' is the good of life in which the things of faith, that is, spiritual truths existing with the Church, are implanted, becomes quite clear from the Lord's parable about the sower in Matthew,

A sower went out to sow, And as he sowed some fell on the pathway, and the birds came and devoured them. Some fell on rocky ground where they did not have much soil, ¹ and immediately they sprang up, since they had no depth of soil ² , but when the sun rose they were scorched; and since they had no root they withered away. Some fell among thorns, and the thorns came up and choked them. But some fell on good soil ² and yielded fruit, some a hundredfold, some sixty, some thirty. He who has an ear to hear let him hear. Matthew 13:4-9; Mark 4:3-9; Luke 8:5-8.

This describes four types of land or ground within the field, that is, within the Church. The fact that here 'the seed' is the Lord's Word, and so the truth which is called the truth of faith, and that 'the good soil' is the good which is called the good of charity is evident to anyone, for it is the good in man that receives the Word. 'The pathway' is falsity, 'rocky ground' is truth which is not rooted in good, 'thorns' are evils.

[3] With regard to the good of life which has its origin in matters of doctrine being meant by 'a man of the field', the position is that those who are being regenerated first of all do good as matters of doctrine direct them, for they do not of themselves know what good is. They learn to do good from matters of doctrine concerning love and charity; from these they know who the Lord is, who the neighbour is, what love is, and what charity is, and so what good is. Those who have come into this stage are stirred by the affection for truth and are called 'men (vir) of the field'. But after that, once they have been regenerated they do good not from matters of doctrine but from love and charity, for the good itself which they have learned about through matters of doctrine exists with them, and they are in that case called 'men (homo) of the field'. It is like someone who is by nature inclined to commit adultery, steal, and murder but who learns from the Ten Commandments that such practices belong to hell and so refrains from them. In this state he is influenced by the Commandments, for he fears hell and learns from those Commandments and similarly from much else in the Word how he ought to conduct his life. In his case when he does what is good he does it from the Commandments. But when good exists with him he starts to loathe adultery, theft, and murder to which he was previously inclined. In this state he no longer does what is good from the Commandments but from the good which by now resides with him. In the first state the truth he learns directs him to good, but in the second state good is the source of truth taught by him.

[4] The same also applies to spiritual truths which are called doctrinal and are more interior Commandments still. For matters of doctrine are interior truths which the natural man possesses, the first truths there being sensory ones, the second truths being factual, and interior truths matters of doctrine. The latter are based on factual truths inasmuch as a person can have and retain no idea, notion, or concept of them except from factual truths. But the foundations on which factual truths are based are sensory truths, for without sensory truths nobody is able to possess factual ones. Such truths, that is to say, factual and sensory, are meant by 'a man skilled in hunting', but matters of doctrine are meant by 'a man of the field'. Such is the order in which those kinds of truths stand in relation to one another in man. Until a person has become adult therefore, and through sensory and factual truths possesses matters of doctrine, he is incapable of being regenerated, for he cannot be confirmed in the truths contained in matters of doctrine except through ideas based on factual and sensory truths - for nothing is ever present in a person's thought, not even the deepest arcanum of faith there, which does not involve some natural or sensory idea, though generally a person is not aware of the essential nature of such ideas. But in the next life the nature of them is revealed before his understanding, if he so desires, and also a visual representation before his sight, if he wants it; for in the next life such things can be presented before one's eyes in a visual form. This seems unbelievable but it is nevertheless what happens there.

Footnotes:

35. Man has two faculties, one which is called the will, and the other the understanding (n. 35, 641, 3539, 3623, 5969, 10122). Those two faculties constitute the very man (n. 10076, 10109-10110, 10264, 10284). The quality of man is according to those two faculties with him (n. 7342, 8885, 9282, 10264, 10284). By them also man is distinguished from beasts, by reason that the understanding of man may be elevated by the Lord, and see Divine truths, and in like manner his will may be elevated and perceive Divine goods; and thus man may be conjoined to the Lord by those two faculties, which make him; but that the case is otherwise with beasts (n. 4525, 5114, 5302, 6323, 9231). And since man may thus be conjoined to the Lord, he cannot die as to his interiors, which are his spirit, but he lives forever (n. 5302). Man is not man from his form, but from good and truth, which are of his will and understanding (n. 4051, 5302).

As all things in the universe relate to good and truth, so do all things in man to the will and the understanding (n. 803, 10122). For the will is the receptacle of good, and the understanding is the receptacle of truth (n. 3332, 3623, 5835, 6065, 6125, 7503, 9300, 9930). It amounts to the same, whether you say truth or faith, for faith is of truth, and truth is of faith; and it amounts to the same whether you say good or love, for love is of good, and good is of love; for what a man believes, that he calls true; and what he loves, that he calls good (n. 4353, 4997, 7178, 10122, 10367). Hence it follows that the understanding is the recipient of faith, and the will the recipient of love; and that faith and love are in man, when they are in his understanding and will, for the life of man is nowhere else (n. 7179, 10122, 10367). And since the understanding of man is capable of receiving faith in the Lord, and the will of receiving love to the Lord, that by faith and love he may be conjoined to the Lord, and whoever is capable of conjunction with the Lord by faith and love, cannot die to eternity (n. 4525, 6323, 9231). Love is conjunction in the spiritual world (n. 1594, 2057, 3939, 4018, 5807, 6195-6196, 7081, 7086, 7501, 10130).

The will of man is the very esse of his life, because it is the receptacle of good, and the understanding is the existere of life thence derived, because it is the receptacle of truth (n. 3619, 5002, 9282). Thus the life of the will is the principal life of man, and the life of the understanding proceeds therefrom (n. 585, 590, 3619, 7342, 8885, 9282, 10076, 10109-10110); comparatively as light proceeds from fire or flame (n. 6032, 6314). Whatever things enter into the understanding, and at the same time into the will, are appropriated to man, but not those which are received in the understanding alone (n. 9009, 9069, 9071, 9133, 9182, 9386, 9393, 10076, 10109-10110).

Those things become of the life of man, which are received in the will, and thence in the understanding (n. 8911, 9069, 9071, 10076, 10109-10110). Every man also is loved and esteemed by others according to the good of his will and thence of his understanding; for he who wills well and understands well is loved and esteemed, and he who understands well and does not will well, is rejected and is held in low estimation (n. 8911, 10076).

Man also after death remains such as his will and the understanding are (n. 9069, 9071, 9386, 10153) and those things which are of the understanding, and not at the same time of the will, then vanish, because they are not in man's spirit (n. 9282). Or, what amounts to the same, man after death remains as his love and its faith are, or as his good and its truth are; and the things which are of the faith and not at the same time of the love, or the things which are of truth and not at the same time of good, vanish, because they are not in the man, thus not man's (n. 553, 2363, 10153). Man is capable of comprehending with the understanding what he does not do from the will, or he may understand what he does not will, because it is against his love (n. 3539).

The will and the understanding constitute one mind (n. 35, 3623, 5835, 10122). Those two faculties of life ought to act as one, that man may be man (n. 3623, 5835, 5969, 9300). How perverted a state they are in, whose understanding and will do not act as one (n. 9075). Such is the state of hypocrites, the deceitful, flatterers, and simulators (n. 2426, 3573, 4799, 8250). The will and the understanding are reduced to one in another life, and there it is not allowable to have a divided mind (n. 8250).

Every doctrinal of the church has its own ideas by which its quality is perceived (n. 3310). The understanding of the doctrinal is according to those ideas, and without an intellectual idea, man would only have an idea of words, and none of things (n. 3825). The ideas of the understanding extend themselves widely into the societies of spirits and angels round about (n. 6599, 6600-6605, 6609, 6613). The ideas of man's understanding are opened in another life, and appear to the life as to their quality (n. 1869, 3310, 5510). Of what quality the ideas of some appear (n. 6200, 8885).

All the will of good and the understanding of truth is from the Lord, but not so the understanding of truth separate from the will of good (n. 1831, 3514, 5482, 5649, 6027, 8685, 8701, 10153). It is the understanding which is enlightened by the Lord (n. 6222, 6608, 10659). The Lord grants to those who are enlightened, to see and understand truth (n. 9382, 10659). The enlightening of the understanding is various, according to the states of man's life (n. 5221, 7012, 7233). The understanding is enlightened as far as man receives truth in the will, that is, as far as he wills to act according thereto (n. 3619). They have their understanding enlightened who read the Word from the love of truth and from the love of the uses of life; but not they who read it from the love of fame, honor, and gain (n. 9382, 10548-10549, 10551). Enlightenment is an actual elevation of the mind into the light of heaven (n. 10330); from experience (n. 1526, 6608).

Light from heaven is the enlightenment of the understanding, as light from the world is to the sight (n. 1524, 5114, 6608, 9128). The light of heaven is the Divine truth, from which is all wisdom and intelligence (n. 3195, 3222, 5400, 8644, 9399, 9548, 9684). It is the understanding of man which is enlightened by that light (n. 1524, 3138, 3167, 4408, 6608, 8707, 9128, 9399, 10569).

The understanding is such as are the truths from good, of which it is formed (n. 10064). The understanding is that which is formed by truths from good, but not what is formed by falsities from evil (n. 10675). The understanding consists in seeing truths, the causes of things, their connections, and consequences in regular order, from those things which are of experience and science (n. 6125). The understanding consists in seeing and perceiving whether a thing be true, before it is confirmed, but not in being able to confirm everything (n. 4741, 7012, 7680, 7950, 8521,8780).

The light of confirmation without a previous perception of truth, is natural light, and may be possessed even by those who are not wise (n. 8780). To see and perceive whether a thing be true before it is confirmed, is only given with those who are affected with truth for the sake of truth, consequently who are in spiritual light (n. 8780). Every dogma even what is false, may be confirmed, even so as to appear true (n. 2243, 2385, 4677, 4741, 5033, 6865, 7950).

How the rational is conceived and born with man (n. 2094, 2524, 2557, 3030, 5126). It is from the influx of the light of heaven from the Lord through the internal man into the knowledges and sciences, which are in the external, and an elevation thence (n. 1895, 1899, 1902). The rational is born by truths, and not by falsities; consequently according to the quality of the truths, such is the rational (n. 2094, 2524, 2557). The rational is opened and formed by truths from good, and it is shut and destroyed by falsities from evil (n. 3108, 5126). A man is not rational who is in falsities from evil; and consequently a man is not rational from being able to reason upon every subject (n. 1944).

Man scarcely knows how to distinguish between the understanding and the will, because he scarcely knows how to distinguish between thinking and willing (n. 9995).

Many more things concerning the will and the understanding may be known and concluded from what has been just adduced concerning good and truth, provided the will be perceived instead of good, and the understanding instead of truth, for the will is of good, and the understanding is of truth.