If you're looking to feel warm and cozy, I wouldn't recommend the Book of Judges. It's a bleak story—a 21-chapter downward spiral featuring deception, oppression, idolatry, murder, gang rape, and apostasy, just to name a few sins. And contrary to what you may recall from that old Sunday school felt board, even its “heroes”—think, say, Gideon and Samson—aren't exactly heroes.
The second in a series of expository guides based on the teaching of Tim Keller, Judges for You: For Reading, For Feeding, For Leading (Good Book Company) seeks to help preachers and laypersons alike understand and apply the message of this pivotal book. (There's an accompanying six-lesson Bible study guide for groups and individuals, also based on Keller's teaching, titled Judges: The Flawed and the Flawless.)
I corresponded with the pastor of Redeemer Presbyterian Church in New York City about the relevance of Judges, why enlightened moderns ought to take it seriously, “Jesus sightings,” and more

A new study on the book of Judges was recently released by The Good Book Company based on your original writings. Perhaps not the most obvious choice! Why is Judges a great book for 21st-century Christians to study?

All Scripture is inspired and profitable, but Judges may be especially profitable for us to read. We see believers living in the midst of pagan communities all around them. The failure of the Israelites to take possession of all the land given to them meant they ended up living in a pluralistic culture. And that's where many Christians find themselves today—we, too, are living in a pluralistic, pagan culture. And we're doing so, in part, because of our own past failures to live and teach as we should have.

On the whole, Judges is a dismal tale of, as one scholar puts it, “progressive deterioration.” What's it doing in the Bible?

Theologically the book shows us human depravity, the weakness of human nature, and the need for a true king and savior. Human beings cannot save themselves; they need a deliverer.

Within scholarly studies there's debate on the main theme of Judges, whether it concerns leadership (anticipating the monarchy) or faithfulness to the Lord (focusing on Israel's idolatry). What are your thoughts on the central message, and how does it affect teaching and preaching the book?

I've always believed it was both themes, pointing to Jesus. Yes, I think the book at one level was written as an “apologetic” for the monarchy in general and David in particular. Without a true king (to use a modern phrase) “things fall apart, the center cannot hold, mere anarchy is loosed upon the world.” But within the entirety of the canon, this message supports the theme that we are sinners who cannot save ourselves, and therefore “salvation is of the Lord”—by his grace and power alone. Though the human author couldn't have consciously foreseen it, Judges points toward the ultimate David and true monarch, Jesus Christ.

The Israelite conquest of Canaan appears to give warrant for imperialism, holy war, and genocide. How can enlightened modern people take a book like Judges seriously?

Yes, in teaching the book of Judges you simply have to deal with this issue—you can't ignore it. And in this brief space I can't even list the issues and the various objections and answers. Maybe the most fundamental thing to say is that if you believe the rest of what the whole Bible teaches—that there's only one true God, that for a period of time he spoke directly to Israel through prophets and through the Urim and Thummim in the priest's breastplate, but that now, since Christ, he speaks to us through his inscripturated Word—then the conquest of Canaan makes sense.

Why? First, God alone has the right to judge people—only he knows what they deserve and what they will do if not stopped. He alone has the right to take a life. Second, in “holy war” Israel did not seek to imperialistically expand its wealth and power but acted as an instrument of God's judgment on a particular set of people. Third, if you believe in the authority of the Bible as the only infallible way to know God's will for us—then holy war today is impossible. God gives no warrant for it. That's what we see when reading the Bible is read as a whole, with the New Testament completing and fulfilling the Old. Jesus specifically forbids Christians to take up the sword in his name, to spread the Christian faith by force. In short, if you believe the rest of the things the Bible teaches, the period of holy war makes sense. Holy war is not, therefore, a reason to reject what the rest of the Bible says about God.

Where is Jesus in Judges?

He's the ultimate judge—the perfect and unflawed Gideon and Samson. He is the ultimate king we don't yet have but whom we need. Even at the terrible end of Judges, where a man gives up his spouse to death to save his own skin, we can't help but think of Jesus our true husband who gives himself up to death in order to save us. Jesus in Judges, as usual, is everywhere.