God Himself told Ephraim to mark their way so that they could return one day to the Promised Land: "Set up signposts, make landmarks; set your heart toward the highway, the way in which you went. Turn back, O virgin of Israel, turn back to these your cities" (Jeremiah 31:21). How were they to do this?
One of the main ways involves the prophecy of Jacob about the tribe of Dan. "Dan shall be a serpent by the way, a viper by the path" (Genesis 49:17). A serpent or snake leaves a mark behind it as it moves over the earth; some snakes, like rattlesnakes, leave very distinctive trails. So does the tribe of Dan.
Though Joshua had allotted land to Dan in Canaan, the Danites found it to be difficult to hold and settle because of its proximity to the Philistines. They began to look elsewhere for living space.
And six hundred men of the family of the Danites went from there, from Zorah and Eshtaol, armed with weapons of war. Then they went up and encamped in Kirjath Jearim in Judah. (Therefore they call that place Mahaneh Dan [Camp of Dan] to this day. There it is, west of Kirjath Jearim.) (Judges 18:11-12)
Finally, they came to the city of Laish, in the far northern reaches of Israel, and they took it. "And they called the name of the city Dan, after the name of Dan their father, who was born to Israel. However the name of the city was formerly Laish" (verse 29).
And thus they have been naming places after their ancestor ever since! A good map of Europe will show dozens of place names carrying the name of Dan within them. The Don, Dnieper, Dniester and Danube rivers all flow into the Black Sea. The Romans knew the Rhine and Rhone rivers as the Eridanus and the Rhodanus. Denmark (literally, "Dan's Land") and Sweden are both northwestern European countries. The English escaped from Dunkirk (literally, "Dan's Church") during WWII. One can find similar place names sprinkled heavily throughout England, Scotland, and especially Ireland, where dun means "judge," just as dan does in Hebrew!
Richard T. Ritenbaugh
Notice how different verses 18-19 sound from anything being spoken by the peoples of Israel today. After Jacob's Trouble, Israel will actually grieve and moan due to the correction she receives. She will beg to be brought back to God. Verse 20 shows the unmistakable compassion and feeling that God has for His people, and His determination to lift them out of the pitiful physical and spiritual condition they will be in at that point.
Verse 21 tells of Israel reversing the course of her migration millennia ago, "Set your heart toward the highway, the way in which you went. Turn back. . . ." Israel comes to this condition and pleads for God's restoration before she makes the Second Exodus, just as Israel cried out in Egypt to the God of their fathers, and then God delivered them. If this is correct, the identity of Israel will be recognized sometime during Jacob's Trouble, but before the Second Exodus takes place.
If the patterns of Israel's history remain consistent, God will remind Israel of her obligation to Him, which will include the knowledge of who Israel is. She will not listen—Israel has rarely listened—so God will cause the nations of Jacob to go through such "trouble" as they have never experienced. Though God does not revel in destruction, He knows best what it will take to turn His people around. In the end, the repentant people who remain will be willingly led back to the Promised Land.
David C. Grabbe
The Second Exodus (Part Three)
Other Forerunner Commentary entries containing Jeremiah 31:21: