Not Just a Piece of Paper

"I don't need the government to tell us what we already know, it's just a piece of paper."

Have you ever heard something similar to this? This view is incorrect according to Scripture. No Christian should hold such a low view of marriage.

Contrary to what you may have heard, marriage is not an arbitrary social construct but is an institution ordained by God. It is a covenant. 

In Ephesians 5, after describing the roles within marriage, Paul explains the meaning of marriage: "Therefore a man shall leave his father and mother and hold fast to his wife, and the two shall become one flesh. This mystery is profound, and I am saying that it refers to Christ and the church" (31-32). This covenant is intended to take two people and join them together into a one-flesh union that lasts until the end of their lives. God ordained marriage from the very beginning, not any government.

"Some of God’s purposes for marriage are companionship (Genesis 2:18), procreation (Genesis 1:28), mutual and undefiled pleasure (1 Corinthians 7:4–5; Proverbs 5:18–19; Song of Solomon; Hebrews 13:4), prevention of immorality (1 Corinthians 7:2, 5), service of Christ, the representation of the spiritual relationship between Christ and the church (Ephesians 5:22–33), and the rearing of godly descendants (Malachi 2:13–16)." [1]

Christians follow His design, His order, His commands.

Marriage is to be between one man and one woman, as described by Jesus in Matthew 19:4-5. He quotes from Genesis 2:24 saying, “have you not read that he who created them from the beginning made them male and female, and said ‘therefore a man shall leave his father and mother and hold fast to his wife, and the two shall become one flesh’?” He goes on in verse 6 to tell us this union is intended to be for life, “so they are no longer two but one flesh. What therefore God has joined together, let no man separate.” Marriage is to illustrate the relationship between Christ and the church, as revealed in Ephesians 5:31-32. Husbands are to love, lead, nourish, provide, and sacrifice for their wives (Ephesians 5:25-26, Colossians 3:18), while wives are to submit to their husbands as to the Lord, be keepers of their home, nurture their children, and be his helper (Genesis 2:18, Ephesians 5:22- 24, Titus 2:5). John MacArthur writes, “Marriage has only one definition, and it is sanctioned by God: the union of one man and one woman (Genesis 2:23-24). Marriage is to be a public, formal, and officially recognized covenant between a man and a woman.” [2]

It is not merely a "piece of paper," it is a binding promise. 

[1] https://www.gotquestions.org/common-law-marriage.html

[2] MacArthur and Mayhue, Biblical Doctrine, 428.