The best thing about chapters 19-21 of Judges is they are the last chapters of Judges. Judges is over, and none too soon. The period of the Judges began when Joshua died and there arose another generation after him who did not know the Lord (Judges 2:10); was characterized by the oft-repeated, "the people of Israel again did what was evil in the sight of the Lord" (Judges 2:11; 3:7, 12; 4:1; 6:1; 10:6; and 13:1); and closes in summary, "In those days there was no king in Israel. Everyone did what was right in his own eyes" (Judges 21:25).
The hope of the book of Judges is that it does end, but God's work does not. God's story continues through Ruth into 1&2 Samuel, when, at last, Israel does have a king, a king after God's own heart, "The Lord has sought out a man after his own heart, and the Lord has commanded him to be prince over his people" (1Samuel 13:14). Even then, the story is far from over, because there is a King to come, the King of kings and Lord of lords, "the only God, our Savior, through Jesus Christ our Lord, be glory, majesty, dominion, and authority, before all time and now and forever. Amen" (Jude 25).
The apostle Paul expresses our hope in God's unfolding story, "And we know that for those who love God all things work together for good, for those who are called according to his purpose" (Romans 8:28). If it's not good yet, God's not done yet.
My Father in heaven, Your kingdom come, your will be done on earth as it is in heaven. I've met the King, my Savior, Jesus Christ, and I will follow Him. May my life display my allegiance, for I am an ambassador of the good news of salvation.
Thank You, God, that You keep working. That what You began, You will finish, and that it will be once-and-for-all good. Keep changing my heart so that I will desire and delight in righteousness and justice and peace. May I love You fully and out of that love, serve the people of this world who so need to know and trust in the Savior, Jesus Christ, my Lord.