The Bible defines marriage as the union between one man and one woman (Matt 19:4-6). Marriage is the first institution ordained by God. The Lord said that it is not good for man to be alone and fashioned woman, to be a wife from Adam’s rib (Gen 2:22-24). The seventh commandment talks about relational intimacy, its primary purpose being to protect marriage. Gay marriage does not adhere to God’s definition of marriage, and is therefore unbiblical.
Marriage is the first human institution. It is designed to model the relationship of Christ to the Church (Eph 5:23-24). Ultimately, marriage is more about holiness than it is happiness. God designed heterosexual marriage for humans in order that they might experience a new understanding of Christ’s love for the Church.
Throughout the Bible, homosexuality is condemned as unnatural, immoral, and an abomination to God (Lev 18:22, Rom 1:26-27). Further, the Bible say that homosexuals shall not inherit the kingdom of God (1 Cor 6:9). Homosexuality is an abomination to God, and gay marriage does not align with the will of God or the original purpose of marriage.
Further evidence that God did not intend for homosexuals to marry is that homosexual intercourse lends itself to a high risk of disease, which is the reward for their error (Rom 1:27). Paul identifies homosexual men as sinners (1 Tim 1:9-10). Men are not permitted to lie with other men, as they would with a woman (Lev 20:13).
God created the institution of marriage to be between one man and one woman so that they may experience pure sexual intimacy, and a better understand Christ’s love for the Church. Homosexuality is condemned throughout the Bible, which states that homosexuals will not inherit the kingdom of God. Thus, allowing homosexuals to marry as designed by God would compromise the sanctity of marriage.