Amos was an herdman/shepherd and farmer before the Lord called him to be a prophet.
Amaziah was a chief priest that led the children of Israel into idolatry.
Amos was called by the Lord to do something that he was not trained to do. Once God calls you he qualifies you. Training is helpful, but the calling on your life from God is what keeps you going when others and everything is against you.
God protects his servants who will obey and work faithfully. The servant of God, must trust and obey, expecting God's next direction.
Amos' response to Amaziah was full of doom.
Amaziah thought Amos was a prophet for the money. Amaziah told Amos that he could earn a comfortable income in Judah. Amaziah told Amos to flee to Judah for his own safety.
Amaziah was not concerned about hearing God's message; he was only worried about his own position. Don't let anything come between you and obeying God.
Are you obeying God's word? Without any special preparation, education, or upbringing, Amos obeyed God's call to "go prophesy unto his people Israel."
Amaziah was the official priest of the royal sanctuary at Bethel.
Not only would the Israelities be taken into exile, but Amaziah's own wife would be a harlot and his sons and daughters would be destroyed.
Reference summary used from The New Oxford Annotated Bible with the Apocrypha Expanded Edition RSV and The Life Application Bible KJV, Tyndale Publishers INC., Wheaton, IL