Just a glance at Amos. 

Bart uses Amos as the oldest book of the Bible to compare to Revelations, which is presumed by some to be the newest, to compare the reasons the God of the Bible punishes the people of the Bible. My prophecy is that his aim is to show how similar these theologies are despite a thousand years time span. 

The book starts out with a timestamp, like many other books do. The timestamp evidence of the naming of the king of Israel and the king of Judah in relation to an earthquake would be typical of an ANE chronicle, for example the Babylonian Astrological chronicle or the Annals of the kings of Israel mentioned in the Dtr. History. The conquests of towns mentioned could be written about any time after those events.

Are the ethics of the poor and the nearly monotheistic power of YHWH representative of ANE texts of 750 BCE Levantine culture?

I must wonder at the ethics based results of Amos compared to proper worship. It reminds me of Cyrus blaming the fall of Babylon (to Cyrus) on the improper worship of Marduk 200 years later. So perhaps this stance on the gods caring for the poor was a special advancement made by the worshippers of YHWH in Israel?

Compared to the Deir Alla inscription dated to 880 BCE- 750 BCE, where we have multiple gaggles of gods perpetuating harm on the region including something similar to an Astarte and a Yahweh, Amos only has variations on the name Yahweh and the term Elohim. This is peculiarly close to a monotheistic ideology.

Comparing Amos to Deir Alla and the ethics of the poor, I would have to wonder if Amos was not written much, much later.