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)

3963. 'Afterwards she bore a daughter' means the affection for all these, and also means the Church of faith in which good is present. This is clear from the meaning of 'a daughter' as an affection, and also as a Church, dealt with in 2363. But as to what the object of the affection is, or what kind of Church is meant, this is evident from whatever is added on to the word 'daughter'. For example, it is evident from the addition of 'Zion' after 'daughter' that the celestial Church, which is called 'the daughter of Zion', is meant; from the addition of 'Jerusalem' that the spiritual Church, which is referred to as 'the daughter of Jerusalem', is meant, and so on. In the present verse, in which nothing is added on to it, 'daughter' means the Church of faith in which good is present. For up to this point the subject has been the general truths which constitute faith in which good is present, and the reception and acknowledgement of those truths, that is to say, the truths that were meant, as has been shown, by the ten sons of Jacob dealt with above. And since immediately after these sons reference is made to the birth of a daughter it is evident from the train of thought that a Church is meant in which all these truths are present.

[2] Whether you call it the Church of faith in which good is present, or you call it the spiritual Church, it amounts to the same; or again if you call it the affection for all these, that is, all these general truths. For it is from the affection for truth in which good is present, and the affection for good from which truth springs, that the Church has its being, not from the affection for truth in which good is not present or the affection for good from which truth does not spring. People who are governed by an affection for truth but not by the good from which truth springs, that is, who do not live according to truths, are much mistaken when they say that they belong to the Church. Though within a congregation, they are outside the Church, for they are governed by the affection for evil to which truth cannot be joined. Their affection for truth does not originate in the Lord but in themselves, for they have themselves in view, their intention being by means of the truth they know to earn repute, and thereby important positions and wealth. But they do not have the Church in view, or the Lord's kingdom, let alone the Lord. But people governed by the affection for good from which truth does not spring do not belong to the Church even though they are within a congregation, for they are governed by natural good, not by spiritual, and allow themselves to be led into every kind of evil and also of falsity, provided that evil is made to look like good and falsity to look like truth, see 3470, 3471, 3518.

161. "'Remember therefore how you have received and heard.'" (3:3) This symbolically means that it should occur to them that all worship in its beginning is natural, and later becomes spiritual through truths from the Word and by a life according to them, and so on.

This is what is these words mean. They also mean that from the Word, from the teaching of the church drawn from the Word, and from sermons, everyone knows that truths must be learned, and that it is through truths that a person has faith and charity and everything else having to do with the church.

[2] The reality of this is something we showed many times in Arcana Coelestia (The Secrets of Heaven), which we published in London. See, for example, the following:

That faith is acquired through truths, nos. 4353 4977, 7178, 10367.

That love for the neighbor or charity is acquired through truths, nos. 4368 7623, 7624, 8034.

That love toward the Lord is acquired through truths, nos. nos. 10143 10153, 10310, 10578, 10645.

That intelligence and wisdom are acquired through truths, nos. 3182 3190, 3387, 10064.

That regeneration is accomplished through truths, nos. 1555 1904, 2046, 2189, 9088, 9959, 10028.

That power against evils and falsities and against hell is gained through truths, nos. 3091 4015, 10488.

That purification from evils and falsities is accomplished through truths, nos. 2799 5954, 7044, 7918, 10229, 10237.

That the church is formed by means of truths, nos. 1798 1799, 3963, 4468, 4672.

That heaven is formed through truths, 6690, 9832, 9931, 10303.

That the innocence of wisdom is attained through truths, nos. 3183 3494, 6013.

That conscience is formed through truths, nos. 1077 2053, 9113.

That order is achieved through truths, nos. 3316 3417, 3570, 4104, 5339, 5343, 6028, 10303.

The beauty of angels is due to truths, and so, too, is the beauty of people as regards their inner qualities which are those of their spirit, nos. 553 3080, 4985, 5199.

That a person is human as a result of truths, nos. 3175 3387, 8370, 10298.

Even so, however, all of these effects are occasioned by truths springing from goodness, and not by truths apart from goodness, goodness that comes from the Lord, nos. 2434 4070, 4736, 5147.

That all goodness comes from the Lord, nos. 1614 2016, 2904, 4151, 5147, 9981.

[3] But who gives any thought to this? Is it not a matter of indifference today whether someone knows this or that truth, provided he attends services of worship? Moreover, because few explore the Word in order to learn truths and live by them, people do not know anything about their worship as to whether it is lifeless or living, and yet it is according to the character of his worship that a person is himself dead or alive.

Of what value otherwise are the Word and doctrine drawn from it? Of what value otherwise are observance of the Sabbath and sermons, or theological treatises? Indeed, of what value otherwise are the church and religion?

That all worship in the beginning is natural, and later becomes spiritual through truths from the Word and a life according to them, is something people know. For a person is born natural, but is taught to become civic-minded and moral, and later spiritual, for thus he is reborn.

All of this is symbolically meant, then, by the directive, "Remember therefore how you have received and heard."