SOUND TO SIGHT: 5 Visions of judgments to come upon Israel (Chapters 7-9).
1. Vision of Locust swarms (7:1-3)
2. Vision of Consuming fire (7:4-6),
3. Vision of the Plumb line (7:7-17)
4. Vision of the Basket of Summer fruit (8:1-14)
5. Vision of the LORD beside the altar (9:1-10)

Amos 7:
The vision (1-9):
God bears long, but he will not bear always with a provoking people. The remembrance of the mercies we formerly received, like the produce of the earth of the former growth, should make us submissive to the will of God, when we meet with disappointments in the latter growth. The Lord has many ways of humbling a sinful nation. Whatever trouble we are under, we should be most earnest with God for the forgiveness of sin. Sin will soon make a great people small. What will become of Israel, if the hand that should raise him be stretched out against him? See the power of prayer. See what a blessing praying people are to a land. See how ready, how swift God is to show mercy; how he waits to be gracious. Israel was a wall, a strong wall, which God himself reared as a defence to his sanctuary. The Lord now seems to stand upon this wall. He measures it; it appears to be a bowing, bulging wall. Thus God would bring the people of Israel to the trial, would discover their wickedness; and the time will come, when those who have been spared often, shall be spared no longer. But the Lord still calls Israel his people. The repeated prayer and success of the prophet should lead us to seek the Saviour. – Mathew Henry Concise Commentary.

In the first two visions, we see two pleads by prophet, and twice God relented.

Vision 1: Vision of Locusts (vs. 1-3) that took away the food supply.

V.1 …locust swarms…: This vision conveyed the strong message from God that the judgment would fall on the land of Israel like a plague of locusts. …late crop… This late crop is wheat following the harvest of Barley. …king’s mowings…: This means the tax for the king is already been collected.
V. 2…forgive, I pray…: Unlike Jonah, Amos doesn’t want to see his prophecy and prediction to happen; so he pleaded.
V. 3…the LORD relented…: God still wants to be patient (Ex. 34:6).

Vision 2: Vision of Fire (vs. 4-6) that took away the water supplies.
V.4 …fire…consumed the great deep and….territory…
V. 5&6…cease,…I pray… This time Amos prayed to God to stop it, and God did relent.

Vision 3: Vision of the plumb line (7-9).
V. 7… Plumb line… A plumb line is a string with a weight fastened to the end of it. When the string is placed beside a wall and the weight is allowed to hang freely, it will be apparent whether or not the wall is perfectly vertical. If the wall is leaning and it is not fixed, it will eventually collapse.

V. 8 …My people Israel… This symbolic vision means Israel had been built according to God’s standards and it will be will be measured/tested by the same standards.…I will not pass by… This time, God says that He will not forgive. It may be that a leaning and a building failed the test by plumb line should be demolished; otherwise it is going to cause more damage when it collapses.
V. 9 …high places and sanctuaries… means Israel is out of line, particularly in its relationship to God.

Amaziah threatens Amos. (10-17)

It is no new thing for the accusers of the brethren, to misrepresent them as enemies to the king and kingdom, as traitors to their prince, and troublers of the land, when they are the best friends to both. Those who make gain their godliness, and are governed by the hopes of wealth and preferment, are ready to think these the most powerful motives with others also. But those who have a warrant from God, like Amos, ought not to fear the face of man. If God, that sent him, had not strengthened him, he could not thus have set his face as a flint. The Lord often chooses the weak and foolish things of the world to confound the wise and mighty. But no fervent prayers, or self-denying labours, can bring proud sinners to bear faithful reproofs and warnings. And all who oppose or despise the Divine word, must expect fatal effects to their souls, unless they repent. – Mathew Henry Concise Commentary.

If the plumb line according to which Israel was constructed was the Torah, then the priesthood should have held Israel accountable to the Torah (Deut. 33:10; Mal. 2:6–7). But the priesthood itself was corrupt (1 Kings 12:31 for how Jeroboam I ruined the priesthood in northern kingdom). Thus, there was no external standard being applied by which Israel’s true condition could be recognized and corrected. In such a case, the end truly was at hand. – ESV Study Bible.

Vs. 10 & 11…Amaziah…: The priests often interfered in the life of the kingdom and functions like the representatives of the established religious leadership. Usually, they have the kings on their side. …Amos has conspired against you… He is accusing Amos as the enemy and the traitor of the king and the kingdom.
V. 12…flee to the land of Judah. There eat bread…: Amaziah thought Amos was a professional priests and make living as a prophet. So, he asked Amos to go to Judah and do his trade.
V. 13…for it is the king’s sanctuary…royal residence…: Though he was the Priest in Bethel, he calls the worship place as the king’s sanctuary, and not as the sanctuary of the King of kings. Amaziah wanted only to hear messages of God’s blessings and success, not message on sin, obedience, and judgment. Read 2 timothy 4:3.
Vs. 14 & 15…no prophet,…sheepbreeder…tender of sycamore fruit…: Amos denies that he is a professional prophet. The LORD took me…and the LORD said to me…(v.15) Amos makes it clear that he is at the command of the LORD.
V. 16…now therefore hear…: Amos is neither discouraged by the words of Amaziah nor felt bad about his background. Rather, he taking authority given by the LORD and commanding Amaziah to hear the word of God in response to his words against Amos.
V. 17…Therefore…: Now, the judgement is not directed to the house of Jeroboam II, but to the family of the priest. Harlot… may means that Amaziah is going to be deprived of food supply that his wife will have to support herself as a prostitute; or at the very least would be violated by the conquerors. …defiled land… a land where he can’t observe the ritual laws of a priest.