Amos - the third in the traditional listing by CHAZAL of the group of Prophets known as the "Trei-Asar," the "Twelve."

A herdsman from Tekoah in Yehudah (Amos 1:1) and declaring that he was neither a Prophet nor the son of a Prophet (Amos 7:14), Amos nevertheless scaled the greatest heights of Prophecy.

For each of "Damesek" (Damascus), Capital of Aram, that destroyed the Kingdom of Israel and exiled the Ten Tribes, "Azah" (Gaza), Capital of the Land of the Philistines, that fought against the People of G-d almost throughout the Biblical Period and stole their Holy Ark, until it was retrieved by David, "Tzor" (Tyre), Capital of Phoenecia, that delivered a captivity to Edom, and "Edom" itself, Amos declares in the Name of HaShem, "For three of your transgressions I would have forgiven you, but not for the fourth."

And then, to show that G-d plays no favorites, Amos cries out to Yehudah and Israel, "For three transgressions I would have forgiven, but not for your fourth!"

And what were the transgressions of the House of Yehudah?

"Thus says the L-rd,
'For three transgressions of Yehudah, I would have forgiven,
But not for four,
Because they have rejected the Torah of G-d,
And have not kept His statutes,
And their lies have caused them to err,
After which their fathers did walk.

So will I send a fire upon Yehudah,
And it shall devour the palaces of Yerushalayim.' "
(Amos 2:4-5)

And the sins of the House of Israel?

"Thus says the L-rd,
'For three transgressions of Israel I would have forgiven,
But not for four,
Because they sell the righteous for silver,
And the needy for a pair of shoes;
…And a man and his father lie with the same woman,
In order to profane My Holy Name!' "
(Amos 2:6-7)

The Prophet gives advice,

"Seek good and not evil, that you may live…"
"Hate the evil, and love the good,
And establish justice in the gate;
It may be that the L-rd, the G-d of Hosts,
will be gracious unto the remnant of Joseph." (Amos 5:14-15)

He declares what HaShem hates,

"Woe to them that are at ease in Zion,
And to them that are secure in the mountains of Samariah…"
"That lie upon beds of ivory,
And stretch themselves upon their couches…"
"That drink wine in bowls,
And anoint themselves with the excellent ointments;
But they are not grieved for the hurt of Joseph."
(Amos 6:1,3,6)

For the result will be disaster,

"The L-rd G-d has sworn by Himself,
Says the L-rd, the G-d of Hosts:
'I abhor the pride of Jacob,
and hate his palaces;
And I will deliver up the city and all that is in it.' "
(Amos 6:8)

But, at the "end of days,"

"In that day will I raise up
The tabernacle of David that has fallen,
And I will raise up his ruins,
And I will build it as the days of old."
(Amos 9:11)

"And I will return the captivity of My People Israel,
And they shall build the waste cities, and inhabit them…
And I will plant them upon their land,
And they shall no more be plucked up
Out of their land which I have given them,
Says the L-rd your G-d."
(Amos 9: 14-15)

According to the RAMBAM, Amos was a link in the Chain of "Mesorah," and received the Tradition of Torah from Hoshea and his court.