From the point of view of modern society where divorce is so common the book of Ruth paints a picture of marriage that is difficult to associate with. Ruth stands by her wedding vows long after her husband is no more. She chooses her husband's side of the family over her own people, her own culture. She shows two features- submission and selflessness- that are often considered weak in a modern woman. Yet reading from the perspective of a Christian believer rather than a woman it is easily understood why the message of Ruth is important.
The message of the New Testament is rooted in submission to the will of God. Jesus, Himself submits to the will of God in the Garden of Gethsamane, setting for us an example to live by His will and not our own. Ruth exemplifies a similar attitude towards the people around her. She submits to God's will in accepting her widowhood and submits to the authority of her mother-in-law. Such submission is not easy and the Book of Ruth shows Naomi's struggle with accepting the fate that had been rendered upon her. Ultimately even Naomi accepted it all and moved on. She learned to love again when she received a son in Obed. Did that erase the pain of losing her husband and two sons? No, definitely not. What it did, however, was that it taught Naomi to live within the will of God.
Another side to Ruth is her selflessness. She could have chosen to be in Moab. She was young and could have found herself a husband, have a family and live among her people, within the culture she grew up in. Ruth however chose to forsake everything familiar to her, with little to no hope for a future, in a nation that did not look kindly upon foreigners. She was not thinking about herself. She was thinking about vows she made to a husband who was no more. She was thinking about an elderly mother-in-law who had lost her entire family. Oftentimes in the modern world, such sentiments are exploited. If Ruth were to exist in today's world she may as well have ended up as a servant to Naomi's relatives rather than as the wife of Boaz and the great-grandmother of King David. The reason is simple. People who care more about others than about themselves are taken advantage of. That is why the world teaches us to know when to put our foot down and learn to say no at one point. Jesus does not give us any similar instruction. He asks us to offer our shirt to the one who asks for our cloak. In short we, as Christians, are asked to go out of our way to help others, despite the consequences.
Ruth sets an example of virtue that does not stem from upbringing. She is a Moabite brought into Israel by marriage. That is a hope for a new believer coming from a family that does not know Christ. If Ruth, the Moabite, can find place in the genealogy of Jesus, then a new believer too, can find place, in the body of Christ, through the redeeming blood of Jesus.