Treatment of An Unloved Wife and The Right Of The Firstborn (Deuteronomy 21:15-17).
The faltering love of a man for a beautiful captive leads on to the case where a man's love for a wife has waned. The stress is on fair treatment and harmony in the family.
Analysis using the words of Moses:
a If a man has two wives, the one beloved, and the other unloved, and they have borne him children, both the beloved and the unloved
b And if the first-born son be hers that was unloved,
b Then it shall be, in the day that he causes his sons to inherit what he has, that he may not make the son of the beloved the firstborn before the son of the unloved who is the firstborn
a But he shall acknowledge the firstborn, the son of the unloved, by giving him a double portion of all that he has, for he is the beginning of his strength, the right of the firstborn is his.
Note in ‘a' that a man has two wives, one beloved and the other not beloved and both bear him children, in the parallel he must acknowledge the true firstborn even if he is borne by the unloved wife. In ‘b' we are told that the firstborn is the son of the unloved wife, and in the parallel we are told that he must not ‘unmake' that situation by favouring the other son as though he were the firstborn.
‘ If a man has two wives, the one beloved, and the other unloved, and they have borne him children, both the beloved and the unloved, and if the first-born son be hers that was unloved, then it shall be, in the day that he causes his sons to inherit what he has, that he may not make the son of the beloved the firstborn before the son of the unloved who is the firstborn.'
The thought of the wife unloved by her husband in verses 10-14 leads on this next regulation. This too applies where a wife is unloved by her husband. In this case the man is a polygamist. Similarly to Jacob he loved one wife, and the other was unloved, even possibly hated. But if they had borne him children, and the unloved one was the mother of his firstborn, he must not disinherit the firstborn for the sake of the second wife's child. He cannot declare that the second wife's son is ‘the firstborn' with all the firstborn's privileges.
Such special rights for the firstborn, and the double portion for the firstborn, are both witnessed to elsewhere in the Ancient Near East.
‘ But he shall acknowledge the firstborn, the son of the unloved, by giving him a double portion of all that he has, for he is the beginning of his strength, the right of the firstborn is his.'
He must rather acknowledge the firstborn and give him the double portion (literally ‘a mouth or two of all that he has' in contrast with one mouthful) which was the firstborn's due. This is because as the firstborn he was the foundation of the man's family, the beginning of what has become his strength. Or alternately ‘strength' may indicate procreative power, thus we may have here the first exercise of his procreative power.
This principle of the special rights of the firstborn is known in other law codes. Esau lost it because he sold it. Reuben lost it because he sinned grievously by taking his father's slave wife (Genesis 49:3-4). But it could only be lost by such illegalities. Kings like David often saw themselves as above this law, but what they were passing on was not a double portion but a throne, and the result was often civil war.
In the case of Abraham Sarah was his first wife. Ishmael was merely the son of a slave wife and thus was not the firstborn.
One lesson for us in this regulation is the need to deal fairly with people and not to indulge in favouritism. It is so easy to favour ‘nice' people, and to disregard those whom we find not so nice. Here God is warning us against such behaviour. We must deal fairly and rightly with all, and not rob people of their genuine rights.
It may be asked, why should the firstborn be given a double portion? Why should everything not be equally divided among members of the family? The reason was a very good and wise one. It was to preserve his status and ensure the continuation of the family. When Israel reached the land, every Israelite family head was to receive a portion of land for the family, and we must remember that family ties were powerful in those days and that families stayed and worked together. So the family head not only had responsibility for his own immediate family but his wider family. There had necessarily to be a family head, and he was usually the firstborn. The firstborn would be the oldest and the most experienced and his being naturally appointed hopefully prevented any falling out about such a position. His authority was automatically recognised.
He would have the responsibility of looking after his mother, any unmarried daughters, and other family adherents and also the family servants. He carried on the family name and had to hold together the wider family. Thus he needed the larger portion. Then if he died without an heir his brother was to raise up a son through the firstborn's wife so that he could inherit the double portion and take over headship of the family. (Whether ‘double' literally meant twice as much or whether it meant such a large portion as was necessary to maintain family unity is open to question). But even though the remainder of the land was passed on to other brothers it was still a part of the family land. If someone sold some of it off it could be redeemed by a kinsman, and whatever happened it returned to the family on the year of Yubile. Had the land simply been divided up on death between all members of the family, soon there would have been lots of tiny pieces of land and total disunity, until some outsider took the opportunity and bought out the lot, and no one would have had responsibility to maintain the family unity. By keeping a large part of the family land together it guaranteed the future of the whole family. If all the males in the family died daughters could inherit but if there were none then the land would pass to near relatives. But it would stay in 'the family'. Family responsibility in those days was taken seriously, was fully binding and along with a sense of tribal responsibility ensured a grouping for self-defence, was for the general benefit and provided a reasonably satisfactory judicial system. The law of primogeniture was therefore of benefit to all for the purpose of maintaining a strong family head. It was only when families ceased to work together that it became a problem, but God was talking to those who recognised the basis of it.