Ruth, a Gentile woman, marries into a Jewish family. when all of the men of the family dies, ruth shows loyalty to her mother-in--law, Naomi, staying with her and scavenging food to keep them alive. As Ruth gleans barley in a filed of the walthy Boaz he takes an interst in her and orders his workers to watch over her. Naomi recognizes Boaz as her late husband's relative and enourages Ruth to pursue him as a "kidsman redeemer," one who weds a realtive's widow to continue a family line. Boaz marries Ruth, starting a prominent family.
Often times people will talk of this story when a woman is waiting for a spouse. This was God's plan that Boaz takes
Ruth as his wife. She pursued him because he was a relative of her late husband. This was under the Law BC.