I do believe this as a basic beginning of what we know as marriage in the christian world.
Genesis 2:18, 21-25
18Then the LORD God said, "It is not good for the man to be alone; I will make him a helper suitable for him."
21So the LORD God caused a deep sleep to fall upon the man, and he slept; then He took one of his ribs and closed up the flesh at that place.
22The LORD God fashioned into a woman the rib which He had taken from the man, and brought her to the man.
23The man said,
"This is now bone of my bones,
And flesh of my flesh;
She shall be called Woman,
Because she was taken out of Man."
24For this reason a man shall leave his father and his mother, and be joined to his wife; and they shall become one flesh.
25And the man and his wife were both naked and were not ashamed.
But however the condition of the world has changed. The state of our human body has changed I believe. People lived hundreds of year at one time. We have changed many conditions of the world because of misuse through the influence of the prince of this world. This world if full of chaos. There is another but.
Our knowledge base is minute compared to our Creators. We only know and understand in part.