Jeremiah presents the people with a stark, undeniable choice regarding their future. Remaining in the Land of Israel guarantees their safety, prosperity, and success, completely removing any need to fear the king of Babylon. Conversely, fleeing to Egypt will bring them nothing but suffering, trouble, and agony [ביאור שטיינזלץ].
The prophet issues severe, repeated warnings to ensure the people fully grasp the consequences of their decision. This intense emphasis highlights two distinct layers of awareness. First, the very act of seeking the prophet's guidance is what sealed their knowledge. Had they never asked for advice, their future might have remained hidden. However, because they specifically requested to know the will of God, they are now fully aware that choosing to go to Egypt will end in their death [מלבי״ם]. Second, the relentless nature of the warning serves a future purpose. It guarantees that when disaster eventually strikes, the people will clearly understand exactly why it happened, remembering that they were explicitly warned in advance [מצודת דוד].