The Book of Ruth is big on loyalty. In fact, the Hebrew word for this—chesed—appears multiple times throughout the story. This word is used elsewhere in the Bible to describe God's loyalty and faithfulness to Israel (source, p. 240). In Ruth, it's the characters who act with chesed towards each other. Ruth shows chesed when she refuses to leave Naomi. Boaz praises her for chesed in the fields. Later, Boaz says that Ruth coming to him on the threshing floor is an act of chesed. Praise the Lord and pass the chesed.