Comfort ye, comfort ye my people, saith your God. Speak ye comfortably to Jerusalem, and cry unto her, that her warfare is accomplished, that her iniquity is pardoned: for she hath received of the LORD’S hand double for all her sins. The voice of him that crieth in the wilderness, Prepare ye the way of the LORD, make straight in the desert a highway for our God. Every valley shall be exalted, and every mountain and hill shall be made low: and the crooked shall be made straight, and the rough places plain: And the glory of the LORD shall be revealed, and all flesh shall see it together: for the mouth of the LORD hath spoken it.
If every mountain is to be lowered and every valley raised up, then we are talking about flattening out the entire surface of earth.
Is this poetic language or a prophecy of major tectonic activity?