"The women said to Naomi: 'Praise be to the Lord, who this day has not left you without a guardian-redeemer.'" — Ruth 4:14
In every clan in Israel the head of the family was considered the guardian-redeemer, responsible for the well-being of the family. This person was expected to rescue, ransom, buy back, recover, or redeem anyone or any property that was in danger of being removed from the family by poverty, war, or death (Leviticus 25:25-55).
Boaz became the guardian-redeemer for Naomi's family, and he was needed to fix two problems: a parcel of land had to be bought back (redeemed), and Ruth needed a husband. Boaz had to do some clever bargaining to redeem the land and marry Ruth, but he was successful, and the story of Ruth ended happily. Ruth gave birth to a grandson for Naomi to preserve her family name. What's more, these people became ancestors of Israel's great King David—and of an even greater king, the King of the world, Jesus Christ.
God, of course, is the real guardian-redeemer in this story. God sent Jesus—a descendent of Ruth and Boaz—to pay the redemption price for our freedom, to restore us to our home in God's family, to rescue us from the evil that threatens us, and to give us a permanent home with him.
God's work in the world is always about redemption; it is always renewing, always loving, always good news.