Question: "What does the Bible say about transsexualism / transgenderism? Is gender identity disorder / gender dysphoria the result of sin?"
Answer: Transsexualism, also known as transgenderism, Gender Identity Disorder (GID), or gender dysphoria, is a desire to change one’s sex or to fulfill the role of the opposite gender. Transsexuals / transgenders usually describe themselves as “trapped” in a body that does not match their gender. They will probably practice transvestism / transvestitism and may also seek hormone therapy and/or surgery to bring their bodies into conformity with their perceived gender.
The Bible has plenty to say about human sexuality. Most basic to our understanding of sex is that God created two (and only two) genders: “male and female He created them” (Genesis 1:27). All the modern-day speculation about numerous genders—or even a gender “continuum” with unlimited genders—is unbiblical.
In Psalm 139, we learn that God fashions each one of us. “For you created my inmost being; you knit me together in my mother's womb. I praise you because I am fearfully and wonderfully made. . . . My frame was not hidden from you when I was made in the secret place. . . . your eyes saw my unformed body” (verses 13-16). God’s creation of each individual must surely include His designation of gender/sex. His wonderful work leaves no room for mistakes; no one is born with the “wrong body.”
After the fall of man, it did not take long for gender issues to become confused. In Abraham’s day, homosexuality was widespread in some cities (Genesis 19:1-7; Jude 7). The Bible is unmistakably clear that homosexuality is a sinful perversion of God’s gift of sexuality (Romans 1:18-32; 1 Corinthians 6:9-10).
In the Law, transvestism / transvestitism was specifically forbidden: “A woman must not wear men’s clothing, nor a man wear women’s clothing, for the Lord your God detests anyone who does this” (Deuteronomy 22:5).
Another possible reference to transsexualism is 1 Corinthians 6:9, where “male prostitutes” is listed as a separate category from “homosexual offenders.” The King James Version uses the word “effeminate” here; that is to say, the “male prostitutes” might be transsexual men who act as women.
No matter if the gender distortion has a genetic, hormonal, physiological, or psychological cause, the Bible clearly and consistently labels any sexual activity outside of marriage or not between a man and a woman as sin, rebellion against God’s plan. But following this realization is good news: sin can be forgiven and lives can be changed through faith in Christ. The Corinthian believers are an example of such a change: “And [homosexuals] is what some of you were. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God” (1 Corinthians 6:11). There is hope for any sinner, transsexuals, transgenders, and transvestites included, because of God’s forgiveness available in Jesus Christ.