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.

217. That in the Word 'vine' means spiritual good and 'fig' natural good is totally unknown nowadays because the internal sense of the Word has been lost. Nevertheless this is what vine and fig mean or embody whenever they occur, as with the Lord's statements in His parables involving a vineyard and also a fig tree, and in the incident recorded in Matthew,

Jesus seeing a fig tree by the wayside went to it but found nothing on it but leaves only; therefore He said to it, Let no fruit from now on ever be born from you! Therefore the fig tree withered at once. Matthew 21:19.

This meant that no good, not even natural good, was found on earth. 'Vine' and 'fig' have the same meaning in Jeremiah,

Were they ashamed that they committed abomination? No indeed, they were not at all filled with shame and they did not know how to blush. Therefore I will surely gather them, says Jehovah; there will be no grapes on the vine, nor figs on the fig tree; and its leaf has fallen. Jeremiah 8:12-13.

This means that all good, both spiritual and natural, had perished, for people were such that they were not even capable of being filled with shame, just as nowadays people governed by evil are so brazen that they even boast about that evil. In Hosea,

Like grapes in the wilderness I found Israel; like the first fruit on the fig tree, in the beginning, I saw your fathers. Hosea 9:10.

And in Joel,

Fear not, you beasts of my fields, for the tree will bear its fruit, the fig tree and the vine will give their full yield. Joel 2:22.

'Vine' stands for spiritual good, 'fig' for natural good.