Malachi writes about 100 years after the Jews return to Jerusalem. It’s the same story of God’s faithfulness to his people and their unfaithfulness to him. The Jews are about to enter into a time when no more prophecies are written. The next great event will be the birth of Jesus 400 years later.
You are probably tired of hearing God’s repeated warnings and the people’s repeated unwillingness to listen to God. Let’s not be guilty of doing the same thing.