 It's a demonstration of 2 Peter chapter 1 and verse 21. For the prophecy came not in old time by the will of man, but holy men of God spake as they were moved by the Holy Ghost. What God equipped Jeremiah with was his inspired, infallible, and errant word. But whatsoever that God was going to command Jeremiah to speak was his word. And he's done exactly the same thing for us.