What was the purpose of prophets in the Old Testament?

God raised up prophets in the Old Testament to direct the nation of Israel in the ways of God.  Prophets were a connection from God to Israel and explained God’s will to them.  This was a different function than that of the priest who connected Israel to God and pled for the covering of their sins.  The first prophet of the Old Testament to Israel was Moses, the great lawgiver.  The first prophet of major significance after Moses was Samuel, who directed the nation of Israel as a judge and tried to mentor King Saul in the paths of God.  Many prophets came and went throughout Israel for hundreds of years and were responsible for revealing God’s word, plans, promises, and curses.