The only biblically consistent way to speak of “sexual orientation” is to recognize that sexual desires and behaviors do occur in deep and persistent patterns. These patterns may be so deep as to feel natural. But the same is true of other sins: it is “natural” for us sinners to be proud, greedy, angry, and so on. None of these sins, however, are “natural” in the sense that that they are normal and right behaviors for humans.
“Sexual orientation” refers to an innate, unchangeable trait that makes it natural and normal for someone to engage in certain sexual practices. The term functions as both an explanation and a defense of homosexuality:
Explanation: People naturally seek sexual unions that fit their orientation. Those with a “heterosexual orientation” will naturally seek sexual union with a person of the opposite sex, while those with a “homosexual orientation” will seek sexual union with a person of the same sex.
Defense: Orientation is an innate and unchangeable trait, like height or skin color, and therefore outside the realm of moral evaluation.
However, the idea of sexual orientation fails in both respects. To take the second point first, let’s grant the (unproven) claim that there are certain biological correlations with homosexual behavior. It does not follow from this that homosexual behavior cannot be evaluated morally. The reason for this is that there are biological correlations to many human behaviors that are clearly subject to moral evaluation. For instance, men are much more likely to commit murder than women. This does not mean that a moral criticism of murder is sexist. Nor does it mean that “men are murderers” because of some innate and unchangeable trait. Human behavior is complicated, and biology is one factor.
Second, the notion of “sexual orientation” fails as an explanation of homosexuality. Unlike height, skin color, or sex, sexual orientation is not observable. It can only be discerned by observing a person’s behaviors and statements. It is therefore at least possible that “orientation” is a concept developed to justify certain sexual behaviors, rather than a real explanation of them. That possibility was already there in the early days of gay and lesbian ideology, but it has emerged as a distinct probability as LGBTQ+ ideology has evolved.
Let me explain what I mean. Consider the phenomenon of “bisexuality” (the “B” in the expanding acronym). Is this an orientation in its own right, or does it describe someone who moves back and forth between two orientations? Such questions are even murkier when “gender-fluid,” “non-binary,” “trans,” “queer,” and various other identities are thrown into the mix. No longer are we talking about an innate, unchangeable trait that makes certain sexual behaviors natural. Rather, we are talking about completely decoupling any evaluation of sexual behavior from innate natural traits.