And if you say in your heart, 'How may we know the word that the LORD has not spoken?'-- when a prophet speaks in the name of the LORD, if the word does not come to pass or come true, that is a word that the LORD has not spoken; the prophet has spoken it presumptuously. You need not be afraid of him.

The prophets who preceded you and me from ancient times prophesied war, famine, and pestilence against many countries and great kingdoms. As for the prophet who prophesies peace, when the word of that prophet comes to pass, then it will be known that the LORD has truly sent the prophet."

Say this to them, Thus says the Lord GOD: As I live, surely those who are in the waste places shall fall by the sword, and whoever is in the open field I will give to the beasts to be devoured, and those who are in strongholds and in caves shall die by pestilence. And I will make the land a desolation and a waste, and her proud might shall come to an end, and the mountains of Israel shall be so desolate that none will pass through. Then they will know that I am the LORD, when I have made the land a desolation and a waste because of all their abominations that they have committed. read more.
"As for you, son of man, your people who talk together about you by the walls and at the doors of the houses, say to one another, each to his brother, 'Come, and hear what the word is that comes from the LORD.' And they come to you as people come, and they sit before you as my people, and they hear what you say but they will not do it; for with lustful talk in their mouths they act; their heart is set on their gain. And behold, you are to them like one who sings lustful songs with a beautiful voice and plays well on an instrument, for they hear what you say, but they will not do it. When this comes--and come it will!--then they will know that a prophet has been among them."