Hi:

Marriage (my wife and I have been married 50 years), is stated clearly in
Genesis 2:24.

                "Therefore a man shall leave his father and mother and be
joined to his wife, and they shall become one flesh."

It is to be a forever arrangement.  Matthew 19:6.

                "So then, they are no longer two but one flesh. Therefore
what God has joined together, lot not man put asunder."

There is a lot of controversy, as to whether their should be a ceremony
before a judge, justice of the peace, or a minister.  In my view,
Israel's history shows there was a religious ceremony when two people
(man and woman) were wed.  We were married in church with a hundred
people or so present.  Also, I believe (my opinion, and I believe
Biblical teaching), that living together does not constitute a marriage.