While the Bible does address homosexuality, it does not explicitly mention gay marriage/same-sex marriage. It is clear, however, that the Bible condemns homosexuality as an immoral and unnatural sin. Leviticus 18:22 identifies homosexual sex as an abomination, a detestable sin. Romans 1:26–27 declares homosexual desires and actions to be “shameful” and “unnatural.” First Corinthians 6:9 states that homosexuals are “wrongdoers” who will not inherit the kingdom of God. Since homosexuality is condemned in the Bible, it follows that homosexuals marrying is not God’s will and would be, in fact, sinful.
Every mention of marriage in the Bible refers to the union of a male and a female. The first mention of marriage, Genesis 2:24, describes it as a man leaving his parents and being united to his wife. In passages that contain instructions regarding marriage, such as 1 Corinthians 7:2–16 and Ephesians 5:23–33, the Bible clearly identifies marriage as being between a man and a woman. Biblically speaking, marriage is the lifetime union of a man and a woman, primarily for the purpose of building a family and providing a stable environment for that family.
The biblical understanding of marriage as the union of a man and a woman is found in every human civilization in world history. History thus argues against gay marriage. Modern secular psychology recognizes that men and women are psychologically and emotionally designed to complement one another. In regard to the family, psychologists contend that a union between a man and woman in which both spouses serve as good gender role models is the best environment in which to raise well-adjusted children. So psychology also argues against gay marriage. Anatomically, men and women were clearly designed to fit together sexually. The “natural” purpose of sexual intercourse is procreation, and only a sexual relationship between a man and a woman can fulfill this purpose. In this way, nature argues against gay marriage.
So, if the Bible, history, psychology, and nature all argue for marriage being between a man and a woman—why is there such a controversy today? Why are those who are opposed to gay marriage/same-sex marriage labeled as hateful people or intolerant bigots, no matter how respectfully the opposition is presented? Why is the gay rights movement so aggressively pushing for gay marriage/same-sex marriage when most people, religious and non-religious, are supportive of gay couples having the same legal rights as married couples through some form of civil union?
The answer, according to the Bible, is that everyone inherently knows that homosexuality is immoral and unnatural. Romans 1:18–32 says that God has made the truth plain. But the truth is rejected and replaced with a lie. The lie is then promoted and the truth suppressed. One way to suppress the truth is to normalize homosexuality and marginalize those who oppose it. And a good way to normalize homosexuality is to place gay marriage/same-sex marriage on an equal plane with traditional, opposite-gender marriage.
To sanction gay marriage/same-sex marriage is to approve of the homosexual lifestyle, which the Bible clearly and consistently labels as sinful. Christians should stand firmly against the idea of gay marriage/same-sex marriage. Further, there are strong, logical arguments against gay marriage/same-sex marriage from contexts apart from the Bible. One does not have to be an evangelical Christian to recognize that marriage is between a man and a woman.
According to the Bible, marriage is ordained by God as the lifetime union of a man and a woman (Genesis 2:21–24; Matthew 19:4–6). Gay marriage/same-sex marriage is a perversion of the institution of marriage and an offense to the God who created marriage. As Christians, we do not condone or ignore sin. Rather, we share the love of God and act as ministers of reconciliation (2 Corinthians 5:18). We point to the forgiveness of sins that is available to all, including homosexuals, through Jesus Christ. We speak the truth in love (Ephesians 4:15) and contend for truth with “gentleness and respect” (1 Peter 3:15).