Ruth 4:13
So Boaz took Ruth, and she was his wife: and when he went in unto her, the LORD gave her conception, and she bare a son. So Boaz took Ruth, and she was his wife: and when he went in unto her, the LORD gave her conception, and she bare a son.
The marriage was accompanied by public formalities, pledges, and covenants, and it was followed by the birth of a son. Taking Ruth as wife fulfilled the nearest kinsman's duty to preserve the deceased man's name and inheritance by raising up offspring for him. The Lord gave Ruth conception and a son, Obed, in reward of her fidelity, faithfulness, virtue, and dutiful love. That son was Obed, who became the father of Jesse and the grandfather of David, so that through Obed Ruth entered the royal line leading to Israel's kings. Through Jesse and David this union began the family line to Christ the Messiah and Saviour, the family line through which Jesus was a direct descendant of Abraham.
Ruth the Moabitess was a Gentile from among the heathen who was gathered to Israel, becoming a proselyte and being fully inducted as a citizen with the rights of native Jews through marriage to Boaz and the birth of her son. In making the Moabitess Ruth a progenitor and ancestor of the Lord according to the flesh, the verse shows God's care for the Seed. Her inclusion proves that Gentile blood was introduced into Jewish veins under the Mosaic system and that the truth and altars of God were made accessible to Gentiles, as the first fruits of their future grand gathering in Christ Jesus and an example of God's continual work of calling Gentiles out and joining them to his people.
Boaz as the near kinsman is a type of the Lord. The marriage is a simple, romantic example of the sacred institution ordained by God, in which marriage is honorable and associated with companionship and mutual good, belonging to the sweet, simple home life among the children of Israel set forth in the pastoral book of Ruth. The marriage bond also serves as a symbol of the union of Christ with the individual believer, with the church, and with his everlasting kingdom.