The Lords way of teaching us in to use Prophets. Beginning with Adam the Lord has continually sent Prophets to teach light and truth. The Lord chooses righteous men for this responsibility. They are not perfect men, just ordinary men who speak for God. Another way to say it is that they are revelators who that declare the will of God, to teach the people whether it is accepted or not. He may foretell future spiritually or temporally. They also bear witness of God. There are also false prophets, you can recognize them by how they live, what they say and do and act.