You can read the relevant post here.

I, generally speaking, agree with Doug’s thoughts on the passage. Regarding the specific question of why the story of the Danite Migration is in the Bible in the first place, Doug is right on: it explains why Dan’s territory is in the north, as well as discounting the cult site at the titular town. To be certain, the author of Judges, as he has throughout the rest of the book, is coloring things so as to get across a point. That point is, I believe, that everyone does what is right in their own eyes. In fact, I might put a little more emphasis on that particular reason for this story’s place in Judges than Doug seems to. The whole point of this story, and the story in the chapters that follow it, is to show how brutal and horrible Israel was. No doubt Dtr wanted to depict people who may have “meant well” but in fact defied YHWH; much like those in his own day.

Perhaps the more fascinating issue for me is the fact that so few of those who claim the book of Judges as part of their foundational document, have ever read and wrestled with the stories in the closing pages of the book. That is to say, your average church-goer (perhaps also your average synagogue-goer?) has no clue that there even is a Judges 17 and following, let alone what said chapters contain. As a Christian, I would very much like to see this material engaged with in the Church.

If one wishes to talk of application for today, it seems somewhat obvious to me: people still do evil things in the name of a God, but one can hardly blame such acts on the deity. Free will is, after all, a rather important part of being human.