Amos 2:6-10,13-16; Psalm 49(50):16-23; Matthew 8:18-22
There are two kinds of Prophetical writings - those where the prophetic tradition was passed down auraly and later written down ('non-literary prophets') and those who wrote books of their own prophesy to hand on, such as Amos, today's first reading author. Actually the distinction is muddier than that - for example Amos almost certainly did not write the final part of the book of Amos, as the literary style changes somewhat.
In either case it is important to appreciate that Old Testament Prophecy is in no way meant to be a prediction of future events. It so happens, that much of the prophetic writings we have do predict actual events that we can seen the historical record and in archaeology. However - the prophets are often written down after the event has taken place - so we need to think more of OT prophesy as teaching us how to think and feel about situations and events.
Amos then is not so much predicting the downfall of Jerusalem, as warning us that continuing to behave badly will lead to a painful outcome. Overall, Amos's message is against the behaviour of those lucky few who hold all the resources in their control, and that we must change and become generous in our support of others. In Samaria, the capital of Israel, archaeologists have found grand houses of the date Amos was writing, built over the ruins of poorer housing, ‘bulldozed’ to make way for them. We can see this kind of behaviour in our country today - if you have a copy to hand their is a good discussion of this trend in a recent copy of 'The Big Issue' that deals with tearing down 1960's housing estates, the homes of communities of relatively poor people, to be replaced with popular and profitable commuter belt housing. The just thing to do would be to refurbish and improve the existing housing, maintaining the communities therein.
Prophets, with their uncompromising words, often create enemies. Jesus talks in Matthew 8 of this today - foxes and birds have their homes, but those who follow The Lord will have none. Yet -we are called to be prophets.