Ruth 4:12
And let thy house be like the house of Pharez, whom Tamar bare unto Judah, of the seed which the LORD shall give thee of this young woman. And let thy house be like the house of Pharez, whom Tamar bare unto Judah, of the seed which the LORD shall give thee of this young woman.
The blessing wished that the household of Boaz would become like the household of Pharez, whom Tamar bore to Judah, through the offspring the Lord would give him by Ruth, the young woman. It was spoken by the elders over the marriage, joining that union to the family line of Judah and looking forward to descendants as the Lord's gift. That union became part of the ancestry leading to David and to Christ.
The blessing belongs to the gate ceremony in which Boaz acted to redeem the family of Elimelech. Before ten elders he offered the nearer kinsman with better right the redemption of Elimelech's parcel of land, on the condition that taking Naomi's field meant also taking Ruth the Moabitess, wife of the dead Mahlon, to raise up the name of the dead upon his inheritance. Naomi had recognized Boaz as of Elimelech's kindred and a Goel, and though willing he found one nearer of kin; the duty to take the childless widow and raise up seed to the dead belonged not to a brother only but to the nearest kinsman as Goel. When that nearer kinsman refused and yielded his right by drawing off his shoe, Boaz bought all that had belonged to Elimelech and Chilion and Mahlon and took Ruth the wife of Mahlon to be his wife, to raise up the name of the dead upon his inheritance so that the name of the dead would not be cut off from among his brethren and from the gate, with the elders and people as witnesses.
The transaction illustrates the law for redeeming men and their inheritances when an Israelite had lost his inheritance or had himself been brought into bondage. Redemption was first by himself if able, and if he was not able then by his nearest of kin in blood-relationship who was able, not merely one near of kin but the one nearest of kin. That nearest able blood-relative bore also the duty to take the childless widow and raise up seed to the dead. Marriage in this setting was publicly recognized through custom and ceremony, including the bride's passage from her father's house to her husband's household, solemn pledges, and a covenant witnessed by others.
The invocation of the house of Pharez connects the marriage of Boaz and Ruth with the family line begun by Tamar and Judah. The closing genealogy traces that line through Ruth, a Moabite woman, as the ancestry leading to David and to Jesus in His human lineage. It belongs to the account of God's care for the promised Seed, with Ruth becoming one of the ancestors of Jesus. The redemption itself typifies the Lord, for fallen humanity has lost its inheritance and is itself in bondage and cannot redeem itself or its inheritance, and must be redeemed by its nearest blood-relative who is able. Jesus Christ alone in all the universe is able, and therefore took part of the same flesh and blood as the children of men in very substance to become their nearest of kin by blood-relationship and their closest kin.