'Prophesy' in the Bible

And he said unto me, Thou must prophesy again before many peoples, and nations, and tongues, and kings.

And I will give power unto my two witnesses, and they shall prophesy a thousand two hundred and threescore days, clothed in sackcloth.

They have power given to them to seal up the sky, so that no rain may fall so long as they continue to prophesy; and power over the waters to turn them into blood, and to smite the earth with various plagues whenever they choose to do so.