The prophet was shown a basket of summer fruit in a vision. As that fruit had come at the end of summer, so had Israel come to the end of their days.
In addition to worshipping idols, Israel was guilty of oppressing the poor in various ways instead of protecting and caring for them as required by the Law of Moses.
Their punishment for disobeying God would be very intense according to the words of Amos. In addition to being intense, Israel’s punishment would be thorough. There would be no escaping. They had enjoyed the privilege of being God’s chosen people, but He also cared for other nations. God has an undying love for all people. He also does not tolerate sin. There was/is a price to pay for sin.
As Amos concluded his prophecy against Israel, he relayed a promise of redemption from God. However, that promise was a spiritual promise instead of physical. Gentiles would also be subjects of that new kingdom that had been promised to David many years earlier.