The Bible speaks directly to "homosexual behavior" or "homosexual acts." A "homosexual", from a scriptural perspective, is someone that chooses to engage in homosexual acts.
Homosexuality as an "identity" is a modern non-biblical construction. Modernists (and post-modernists) began to assert that homosexual behavior is genetically based (e.g. a genetic flaw in the human genome) and then fabricated an identity around this immoral behavior.
Understand; however, that despite intensive investigation into the human genome by the scientific community: they have failed to find "gay genes." The reason why they have failed to find "gay genes" is because they don't exist. Homosexuality is not a behavior that's written into the DNA of the human genome even as a genetic defect.
As a result, researchers studying "homosexuality" are now hypothesizing that homosexual behavior is a genetic expression (e.g. modifications to how and when DNA is activated by environment and by behavior) which is a field of study called epigenetics (e.g. the study of inherited gene expressions caused by means other than changes in DNA sequence specifically changes that have occurred in heritable information but are not caused by changes in the DNA molecule).
They are hypothesizing that that “sexually antagonistic” epi-marks, which normally protect parents from natural variation in sex hormone levels during fetal development, sometimes carryover across generations and cause homosexuality in opposite-sex offspring.
The theory is hypothesizing that homosexuality is a side effect of the epigenetic canalization of sex differences in which homosexuality itself is assumed to impose a fitness cost which is outweighed by the benefit of locking in sexual preference in cases where reprogramming is successful (or unnecessary).
But understand that this is an unproven theory to date with correlation (X causes Y) unproven. And, epigenetic changes are not random but rather occur in response to environment. Nurture and the behaviors one chooses to engage in effect a physiological plasticity upon one's susceptible genetic expression in this theory.
In purely biblical terms, specifically Romans 1, people who choose to engage in homosexual acts (whether some predisposition for it actually exists or not) are choosing to "exchange" God’s purposes for unnatural purposes.
Even if a predisposition toward a homosexual behavior does exist in some people, they have the ability to choose not to engage in it just as they have the ability to choose to engage in a heterosexual behavior. The existence of a predisposition does not equate to machine programming in which people act like robots carrying out instructions without any choice in the matter as so many falsely assert today.
I have a normal sex drive and I've been celibate for 26 years. We are not robots.
The choice to engage in heterosexual acts, homosexual acts, or abstinence with regard to other people is a real choice that exists with each of us. We CAN choose.
The biblical warning for people who choose to engage in homosexual acts is, whether or not a genetic disposition actually exists, if they choose to rebelliously engage in homosexual acts without repentance they can eventually become consumed to the point of reprobation at which point God lets go giving them up to their lusts (Rom 1:18–25).
While references to homosexual acts are limited in Scripture, they become a powerful image for those who in their rebellion and blindness choose to give up God’s good gift of normative morality in healthy sexuality and exchange it for something degrading and unnatural.
Homosexual acts become a symbol in Scripture for violating a basic principle of holiness: mixing that which the Lord declared should be separate.
In Romans 1, Paul condemns homosexual acts, lesbian as well as male, in the same breath as idolatry (vv. 23–27), but his theological canvas is broader than that. Instead of treating homosexual behavior as an expression of idolatrous worship, he traces both to the bad ‘exchange’ fallen man has made in departing from his Creator’s intention. Seen from this angle, every homosexual act is unnatural, because it flies in the face of God’s creation scheme for human sexual expression.
People are not girls trapped in boys bodies and boys trapped in girls bodies as those the devil deceived falsely assert in gender diversity. They are sinners trapped in a world that sin has permeated and need salvation followed by sanctification.
It is one thing to repent and become a Christian in recovery/sanctification struggling with sin issues in their life. This is the condition many Christians find themselves in. Perhaps all, to some extent. These are born-again and have aligned themselves with God in truth.
It is entirely another thing to justify one's sin as normal and refuse to repent aligning with ungodliness in rebellion to God and then twisting His Word to "justify" it deceiving themselves and others as per 2 Timothy 12-13:
"In fact, everyone who wants to live a godly life in Christ Jesus will be persecuted, while evildoers and impostors will go from bad to worse, deceiving and being deceived."
Thanks everyone for your answers, I do need more Christian friends. Just recently joined a church. My husband refuses to go, so I go alone, but I'm hoping to join a small group & get to know people.
I am a little confused about the first answer though, where it says the act of homosexuality is a sin, but being homosexual is not... How is that possible? Is that true?