Ruth and Esther, the only two biblical books that centre on the lives of women, display the hand of a God who works in the lives of individuals to bring about his plan for the salvation of many. Ruth is an outsider who finds a home among the people of God and whose descendants include not only King David, but David's greater son, Christ the King of Kings.
While Ruth's story focuses through the mundane dynamics of a peasant family, Esther's story plays out in the palace precincts of a despotic king. While God's name is famously never mentioned, we see his handiwork in each twist and turn of the narrative. He uses improbable means and improbable individuals to save His people, and we see that God is on His throne.
Focus on the Bible commentaries are popular level commentaries especially useful for pastors and small group leaders. They are also useful for personal devotions and spiritual growth. The series holds to the inerrancy of scripture and the uniqueness of Christ in salvation.