A pre-nuptial agreement signed before their 1999 wedding will see Ms Deng benefit handsomely (but not too handsomely) from the split - Mr Murdoch's second wife Anna Maria Torv reportedly received a $US1.7 billion divorce settlement in 1999 at the end of their 31 year marriage.

Yes, that was the same year Mr Murdoch went on to marry Ms Deng.

Money. Power. Beauty. Convenience.

Marriage was never meant to be like this.

The divorce rate in Australia is about 43 per cent - that is, 43 per cent of marriages can be expected to end in separation within 30 years (Australian Bureau of Statistics).

And I don't need to tell you of the damage that divorce inflicts - not only on the couple but also on children and extended family.

I am convinced that the true definition of marriage has been allowed to slide. Over time, some definitions will change - it's the nature of the English language. Some words - like "bully" - have even come to mean the direct opposite of their original expression. In the 16th century, "bully" was a term of endearment. By the 17th century, that definition had morphed to mean braggart, a show- off. Another hundred years and the "bully" is what we know today - tormenter of the weak.

A bedrock institution like marriage, the foundation of society, should never be permitted to slip and slide within the English lexicon.

What is marriage, or rather, what was marriage?

Marriage is a covenant.

At some point, people started calling marriage a contract rather than a covenant. The difference, you ask?

A contract has limited liability. It binds the parties within particular terms and conditions. A contract marriage might look like this:

"I will honour our marriage as long as you contribute to the household income, as long as you don't cheat on me, as long as you remain fit and handsome and as long as you keep me happy."

A marriage with a pre-nup is a contract marriage. It's saying: "This marriage could fail - and if it does, I don't want this woman/man getting my stuff!"

A covenant marriage, however, has unlimited liability. There's no "mine and yours". There are no escape clauses and the only conditions are "for richer or poorer, in sickness and in health"; the only terms "until death do us part".

The Bible calls this joining of man and woman a "one flesh" exchange.

"For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh. So they are no longer two, but one flesh. Therefore what God has joined together, let no one separate." (Matthew 19:5-6)

When a tribe makes a covenant with another tribe, representatives usually seal the agreement by mixing their blood. It's why the campaign of explorers Stanley and Livingstone was so successful. Stanley made a covenant with a powerful African chief so that whenever he revealed the scars (the sign) of their covenant exchange, he was treated with great reverence. That covenant told people that Stanley was one with the most powerful tribe in Africa - their resources were at his disposal.

That's the strength of covenant. Two become one, committed to each other no matter what. They lay down their weapons against each other. They defend each other as if the attack was on their own flesh. All their resources are pooled. They are one.

A wedding ring should express the same as the scars from an African blood covenant. Marriage is a vow (Ecclesiastes 5:4-7), a covenant not to be taken lightly, and God honours marriage vows (Ecclesiastes 4:9-12).

Marriage is society's main artery - it must be defended against trends and throw-away attitudes.

Read more of Claire van Ryn's musings at faithlikeamushroom.wordpress.com, tweets to @ClairevanRyn.