Jeremiah 5:13

There were many prophets in both kingdoms whose alleged prophecies were nothing more than hot air (wind, Heb. ruah, also translated "spirit"). They did not utter the Lord’s words. God indeed would bring judgment on His people.

"The essence of true prophecy was the spirit of God, but such was their blindness, or willful ignorance, that they could not discern between wind and the true spirit of prophecy." [Note: Craigie, p. 92.]