What is a prophet?
A prophet makes a new world by the power of his words alone. This is why he arises at the end of an era: because he creates the next era. A prophet never comes with the power of the sword: that is the power of kings, and they are supposed to use it. The prophet, however, uses his words only. Kings don’t create new worlds: kings drive out the evil in the existing world and protect and guard the righteous. They pass judgment. But a prophet is responsible for bringing this world into existence, and when its time comes, they destroy it and make a new one, using their words.
A prophet restores true memory. Deuteronomy consists of Moses’ sermons reminding Israel of their true history. History often gets perverted and twisted around, but a prophet sets the record straight. This is why the books of histories in the Bible are all written by prophets. Moses, Samuel, Jeremiah, Daniel, etc. They restore the true history. Only a prophet of God can truly write history; history is a story, and they can see the overarching narrative. Everything else is just chronicles: a list of facts and things that happened; there’s no real coherence or underlying theme evident.
A prophet prepares a king for death. The ultimate point of a king is for him to die for his people. Either he goes willingly and brings great blessing to his people (and is resurrected), or he goes unwillingly (and this is often actual, physical death). The book of Daniel is primarily about Daniel preparing Nebuchadnezzar for his death. Nebuchadnezzar fails to listen, and as a result, becomes a beast before being restored. Prophets not only aid kings, but also entire peoples in their death/resurrections. Moses did it with Israel in the wilderness, and Daniel and others did it during the Babylonian captivity. The prophet guides the people and the king through this extremely trying time: without him, it’s nigh impossible to make it to the other side.
A prophet arises when people call evil good and good evil (as seen in Proverbs and Isaiah especially). He uses his wisdom to restore those boundaries. This is connected with his role of restoring memory, as well as his role of making a new world by his words alone.