Love is not enough. In a parasha laden with laws, one in particular is full of fascination.

Here it is. If a man has two wives, one loved, the other unloved, in Hebrew Sanua, which literally means hated.

And both the loved and the unloved bear him sons.

But the firstborn is the son of the unloved wife, then when he wills his property to his sons,

he mustn't give the rights of the firstborn to the son of the beloved wife, in preference

to his actual firstborn, the son of the unloved wife.

He must recognize the legal rights of the firstborn of his unloved wife

so as to give him a double share of all he has,

for he is the first of his father's strength.

The birthright is legally his.

Now the law makes eminent sense. In biblical Israel, the firstborn was

entitled to a double share in his father's inheritance. What the law tells us is that this is not

at the father's discretion. He can't choose to transfer this privilege from one son to another.

In particular, he can't do this by

favouring the son of the wife he loves most if, in fact, the firstborn came from another wife.

The opening three laws. A captive woman taken in course of war, the above war about the rights

of the firstborn, and the Ben-Sorreumura,

the stubborn and rebellious son, are all about dysfunctions within the family.

The sages said that they were given in this order to hint that somebody who takes a captive

woman will suffer from strife at home and the result will be a delinquent son.

In Judaism, marriage is seen as the foundation of society. Disorder there leads to disorder

elsewhere. So far, so clear. But what's extraordinary about it is that it seems to be in the

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