Moabitess, ancestress of King David. Was married to a Jewish emigre from Bethlehem. When he died, she followed her mother-in-law, Naomi, back to Bethlehem, where she caught the attention of Boaz, Naomi's kinsman, when collecting sheaves in his field. He bought Naomi's late husband's property to keep it in the family and married Ruth. David was their great-grandson.
Jewish tradition considers Ruth's reply to Naomi's urging her to return to her Moabite country and people (Ruth 1:16–17) a perfect summary of a proselyte's undertaking.
Ruth is the central figure of the biblical book bearing her name, whose aim, according to the Midrash (Ruth R. 2), is "to teach how great is the reward for lovingkindness." The book contains a description of levirate marriage and halitzah (1:11, 2:20, 4:7ff.). In the synagogue the book is read in the Shavuot (Pentecost) Shaharit service before the Torah reading. Among the explanations for the Shavuot–Ruth connection are: the story takes place in the harvest season culminated by Shavuot; David's birthday and yahrzeit (death anniversary) are traditionally marked on Shavuot; this festival, which celebrates the anniversary of the Revelation of the Torah at Mount Sinai, is an appropriate time to read this idyl whose heroine is a model of a true proselyte's dedication to God, Torah and the Jewish people.