A "field" in the Bible usually represents the Lord's church, and more specifically the desire for good within the church. It's where good things start, take root, and grow. When you have a desire to be a good person and to do good things, the natural first questions are "What does that mean?", "What should I do?", "What can I do?". You look for ideas, concepts, direction. Once you figure out something you want to do or a change you want to make in yourself, you seek specific knowledge. If you want to volunteer at a food pantry, say, you'd need to know whom to call, when they need help, where to go, what to bring. Armed with that knowhow, you're ready to get to work. That process could be compared to food production. You start with a field -- which is that desire to be good. Then you plant seeds -- those ideas and concepts. Those seeds sprout into plants -- the specific facts and knowledge needed for the task (easily seen in the food pantry example, but also true with deeper tasks like "being more tolerant of my co-workers" or "taking more time for prayer," or "consciously being a more loving spouse"). Finally, those plants produce food -- the actual good thing that you go and do. The Writings also say that in a number of cases a "field" represents the doctrine, or teachings, of the church. This sounds markedly different. The desire for good is emotional, a drive, a wanting; doctrine is a set of ideas. But for a church to be true, its doctrine must be centered on a desire for good, and must lead people toward doing what is good. So sound doctrine is actually closely bound up with the desire for good.

1304. That 'let us build ourselves a city and a tower' means that they fabricated a form of doctrine and of worship becomes clear from the meaning of 'a city' and from the meaning of 'a tower', dealt with in the paragraphs that follow this. The Church is such that when charity towards the neighbour departs and self-love takes its place, the doctrine of faith is of no account at all except insofar as it can be converted into worship of self. Nor do people consider that worship contains anything holy unless it exists for the sake of self, thus unless it is worship of self. This applies to all self-love. In fact a person who loves himself more than others not only hates everybody who is not subservient to him and shows no favour to them except when they have become subservient, but also, to the extent that he is not prevented, he plunges even into exalting himself above God. The fact that self-love is such when given free rein I have been shown in actual occurrences. These are the things meant by 'a city and a tower'. Self-love, and every desire springing from it, is of all things the filthiest and most unholy, and is very hell itself. From this anyone may deduce the nature of the worship that has such as this within it.