No one has any authority to define marriage contrary to Scripture, which declares that marriage is a legal and spiritual union whereby one man and one woman become one flesh through means of a covenant.
Marriage is neither a state institution nor a church ordinance. Marriage is a common (though divine) institution and is not unique to the kingdom of Christ (which has been given the ordinances of baptism and the Lord’s Supper). Note that, in today’s world, pastors only have authority to declare a man and woman husband and wife “by the power vested in [them] by the state”.
It is an agreement between two people. Though the terms and conditions are much more solemn, a marriage agreement is not altogether different than any other kind of legally binding agreement between two parties. Just as the state does not issue a license for every agreement people enter into, neither should they nor need they issue a marriage license. The marriage may be performed by family in the presence of witnesses (just as other agreements often require witnesses).
Individuals in a free society are at liberty to honor or reject another party’s marriage. Christians are under no obligation to honor an unbiblical marriage (homosexual or otherwise) but neither may they restrict two parties from voluntarily entering into an agreement.
Christ taught, in light of creation, that it is sinful for a couple to divorce for any reason except sexual immorality (which even then should be conducted in light of Christ’s love for and forgiveness of His bride). Yet because Christians have no legal ground to restrict another couple’s agreement, we must “allow” divorce among non-Christians for any reason of their choosing. Furthermore, we are commanded not to judge the world (1 Cor 5:12) by expecting them to live like us.
Because the state has unjustly taken upon itself a monopoly over the marriage covenant, Christians have found themselves wrongly wielding the carnal sword (state) in disagreements with the world over marriage, rather than being salt and light and waging war with the sword of the Spirit, calling all men everywhere to repentance, and proclaiming the kingdom of God (not the kingdom of America).
Marriage is a divine institution. (1.) Because founded on the nature of man as constituted by God. He made man male and female, and ordained marriage as the indispensable condition of the continuance of the race. (2.) Marriage was instituted before the existence of civil society, and therefore cannot in its essential nature be a civil institution. As Adam and Eve were married not in virtue of any civil law, or by the intervention of a civil magistrate, so any man and woman cast together on a desert island, could lawfully take each other as husband and wife, It is a degradation of the institution to make it a mere civil contract. (3.) God commanded men to marry, when He commanded them to increase, and multiply and replenish the earth. (4.) God in his word has prescribed the duties belonging to the marriage relation; He has made known his will as to the parties who may lawfully be united in marriage; He has determined the continuance of the relation; and the causes which alone justify its dissolution. These matters are not subject to the will of the parties, or to the authority of the State. (5.) The vow of mutual fidelity made by husband and wife, is not made exclusively by each one to the other, but by each to God. When a man connects himself with a Christian Church he enters into covenant with his brethren in the Lord; mutual obligations are assumed; but nevertheless the covenant is made with God. He joins the Church in obedience to the will of God; he promises to regulate his faith and practice by the divine word; and the vow of fidelity is made to God. It is the same in marriage. It is a voluntary, mutual compact between husband and wife. They promise to be faithful to each other; but nevertheless they act in obedience to God, and promise to Him that they will live together as man and wife, according to his word. Any violation of the compact is, therefore, a violation of a vow made to God.
…As the essence of the marriage contract is the mutual compact of the parties in the sight of God and in the presence of witnesses, it is not absolutely necessary that it should be celebrated by a minister of religion or even by a civil magistrate. It may be lawfully solemnized, as among the Quakers, without the intervention of either.
Edmund S. Morgan, in “Visible Saints: The History of a Puritan Idea” notes that the Separatists rejected marriage as a responsibility of the church or its ministers:
Marriages were not a church matter at all and were to be performed by a simple declaration in front of witnesses.
Morgan footnotes Walker’s Creeds and Platforms, which contains “The Points of Difference, 1603” written by Separatists while “in exile” from England:
6. That the Ministers aforesaid being lawfully called by the Church where they are to administer, ought to continew in their functions according to God’s ordinance, and carefully to feed the flock of Christ committed unto them, being not injoyned or suffered to beare Civill offices withall, neither burthened with the execution of Civil affaires, as the celebration of marriage, burying the dead &c, which things belong as well to those without as within the Church. (1)
(1) This article, the last clauses of which are so foreign to modern Congregational sentiment, represents the view also of the founders of New England regarding marriages and funerals. As far as known, the first instance of prayer at a New England funeral was at Roxbury in 1684… The next year, 1686, saw the first marriage by a minister in Mass… Connecticut permitted ministers to join inmarriage by a law of Oct. 1694
(Gordon Clark) opposed government involvement in marriage. According to his son-in-law Clark was opposed to the government being involved in marriage. And even, holding a unique position as far as I’m aware of, that the CHURCH shouldn’t be involved in marriage. I can only speculate that as an aggressive exegete of the scriptures he saw no particular evidence for the church sanctioning marriage, but it being a personal or family affair.
Libertarianism in the Thought of Calvinist Philosopher Gordon. H. Clark
In fact, I would argue that marriage is a creation ordinance, not a church ordinance. I’m not sure that ministers of the gospel should be involved in the legal matters of weddings at all.