Claims of God Being Omnipotent in the Bible

It is a little unclear whether the words of the prophet are put in his mouth by god or he just 'allows' them to come out. Some ethicists would say it's the same thing.
But I don't understand your assertion that the prophecy is true if the prophet is claiming that it came to him from another god. That would be a lie in god's eyes.
Anyway, what about some better verses like:
Ezek 14:9
And if the prophet be deceived when he hath spoken a thing, I the LORD have deceived that prophet, and I will stretch out my hand upon him, and will destroy him from the midst of my people Israel.