This is the question.
The state system does not recognize marriage the way Abe and Sarah determined God defined their marriage. They did not buy a marriage license.
Render unto Caesar the things which are Cesar. Marriage is NOT Ceasar's.
I have heard of Christians who do not get marriage license. 1. They are in severe persecution country. 2. They see no need to pay Ceasar extra money. 3. They believe in covenant marriages (meaning a marriage lasts for life even in separation) 4. The people are under slave conditions and forced to marry 5. The people are under slave conditions and they simply have a broom stick wedding (nothing is signed only witnesses attend).
All that would be needed to pay the state system is the name change. A termination of a marriage would only need a cheaper "name change" rather than expensive divorce routines.
The state does not define marriage the way the bible defines marriage.
However, the bible DOES define that a marriage does not make a person good. Ahab and Jezabel were married, but they were wicked people.
How to define and live a life of marriage?
1. Regular commitment to bible study.
2. Regular prayer for spouse.
3. Regular acts of doing good towards God's people.
4. Regular acts of doing good towards one's spouse.
Those are things that define a marriage. Plain and simple. A wedding ring does not make a marriage work. A "certificate" doesn't make a marriage. A special dress does not make a marriage.
What makes a marriage?
God's word and people's willingness to listen to it.
So when a person says they are "Christian" and they support destroying polygyny or patriarchy or anything that the bible doesn't forbid, then they are not truly "Christian" they are statists who support the rules and laws of the state, they do not support the rules and laws of the bible.