In chapter 4 of the Book of Amos, verses 1-3 are talking about people who pervert the truths of the church. They will fall into falsities in outermost things.

In the Bible, fish represent "lower" things than mammals, so we can interpret the fishhooks in verse 2 as meaning being caught and held fast in natural or lower things.

Verses 4-6 are about acts of worship such as tithes and sacrifices. These look similar to genuine worship, but are only external sorts of things. We can tell because ‘teeth’ (in verse 6) represent ultimates or outermost things (see Secrets of Heaven 6380). It follows that “cleanness of teeth” would mean outermost things that look good but only imitate genuine worship. The Lord exhorts, “Yet you have not returned to me.”

Verses 7-8. Some things true will remain, when where there are too many false ideas, the truths don't get through. This can be seen where the Lord says, “I made it rain on one city; I withheld rain from another city... where it did not rain the part withered.” Again the Lord exhorts, “Yet you have not returned to me.”

Verse 9. Afterward all things of the church are falsified, shown by blight attacking the gardens, vineyards, fig tree and olive trees. The last three represent spiritual, natural and celestial things, or all the things of spiritual life. “Yet you have not returned to me,” says the Lord.

Verses 10-11. The Lord explains the devastating things he allowed to happen: plague in Egypt, death of young men by swords, stench in the camps, Sodom and Gomorrah. This is because they are profaned by sensual knowledges. Profanation means the mixing of good and evil together. (See Secrets of Heaven 1001[2]).

This extends to all things of the church, with the church being the Lord’s kingdom on earth (Secrets of Heaven 768[3]).

With profanation “as soon as any idea of what is holy arises, the idea of what is profane joins immediately to it,” (Secrets of Heaven 301).

Now there is hardly anything left. “Yet you have not returned to Me,” says the Lord again.

Verses 12-13: Because people adamantly remain in their profane ways, they are warned, “Prepare to meet your God!”. This is the God powerful and mighty, “who forms mountains, and creates the wind,” and even more close to home, “Who declares to man what his thought is.” As intimately a knowing as that is, the Lord’s love for all humanity is contained in His exhortations for them to turn themselves to Him.

See, for example, Luke 6:44-45, and True Christian Religion 373.

793. From this point onwards to the end of the present chapter the subject is the people before the Flood who perished. This becomes clear from the details in the description given. People who possess the internal sense can recognize instantly, and indeed from any single word, what the subject is, better still from the combination of many. When the subject changes different words instantly appear, or else the same words combined differently. The reason is that some words are peculiar to spiritual matters, others peculiar to celestial; or what amounts to the same, some are peculiar to things of the understanding, others to those of the will. For example, 'desolation' is a word used of spiritual things, 'vastation' of celestial; 'city' is used of spiritual, 'mountain' of celestial; and so on. The same applies to combinations of words. And what is bound to amaze everybody, the difference in Hebrew is frequently just a matter of vocalization. In what belongs to the class of spiritual words the first three vowels [of the alphabet] are normally prominent, but in the case of what is celestial the last two. The fact that these verses contain a different subject is also discernible from the repetition discussed already. That is to say, the statement, 'And the waters grew stronger and stronger over the earth', is a repetition of what has already been stated in the previous verse. It is also discernible from everything that follows.