The Book of Esther gives us a wonderful view of God's providence. In particular, it shows how God rules and defends his Church in times of great adversity. A remarkable train of events led to the Lord raising up Esther from an obscure position in society to become the Queen of Persia. God then gave her grace to stand firm, at the risk to her own life, so that she might save the Jews from the wicked plot of Haman.
This is a very readable study of Esther's life, and clearly shows us many practical lessons for Christian living. This is particularly useful in our day, when the Church is assailed by many enemies.