Meeting Boaz: Naomi and Ruth have no means of support. So Ruth goes into the fields during the harvest season to glean. Mosaic law requires that the poor be permitted to follow the harvesters and gather grain that falls to the ground when the sheaves are gathered up. Boaz notices the young woman. Knowing of her faithfulness to Naomi and good reputation, he tells her to return to his fields and promises her protection. Privately Boaz tells his workers to leave some stalks in the fields for her to find.
Naomi’s Plan: Naomi urges Ruth to return to Boaz’ fields. Her grim warning is a reminder of the moral condition of Israel: “in someone else’s field you might be harmed.” But Naomi has another reason. Boaz is a relative of her family, and thus a potential “kinsman-redeemer.” This phrase refers to a provision of OT law especially for women whose husbands die and leave them childless. To preserve the family line and the family land, a relative is permitted to marry the widow. The first boy will be counted as son of the dead husband, and the line will thus be preserved.
Ruth’s request in 3:9 is no invitation to an immoral relationship; it is an appeal to Boaz to marry her and perform the duty of a kinsman-redeemer,
And he said, Who art thou? And she answered, I am Ruth thine handmaid: spread therefore thy skirt over thine handmaid; for thou art a near kinsman. And he said, Blessed be thou of the Lord, my daughter: for thou hast shewed more kindness in the latter end than at the beginning, inasmuch as thou followedst not young men, whether poor or rich. Ruth3:9, 10