The sexual orientation theory asserts that a person's sexual preferences are immutable and should therefore be accepted by society,  as theorized by some developmental psychologists and advocated by many social advocates and partisans.
Many social advocates assert that unknown biological factors are responsible for sexual orientation. Thus, they argue that is by no means a matter of choice, and that it is pointless to try to change one's orientation. Some go so far as to say that the attempt would cause harm, so mental health professionals must not offer assistance even if asked.
In contrast, sexual preference refers to a person's preferred mode of sexual activity, fantasy or desire.
Advocates of homosexuality frequently argue that sexual orientation is fixed at birth, i.e. one is "born that way". This forms the basis of an argument that homosexuality is not a matter of choice, and thus should not be criticized. One may as well criticize a person for having blond hair, or dark brown skin.
As a response to the claim that homosexual activities are "unnatural" or "do not occur in nature," many groups cite scientific studies that indicate homosexual practices in many species (such as apes, monkeys, or penguins).
Some homosexuality advocates make an intermediate claim, i.e., that sexual orientation is caused by a number of factors but does not become unchangeable until early childhood or even as late as adolescence. Likewise, this forms the basis of the argument that no one can be held morally responsible for being homosexual.
There is no scientific consensus on when sexual orientation is fixed, or whether it is fixed at all. All attempts to find a "gay gene" have failed.
Many people generally disagree with the premises of these homosexuality arguments.
- A person "born" with a strong craving for alcoholic drinks would still be held responsible if he got drunk and injured someone in a car accident.
- A person with an "inherent" hatred of blacks would still be considered a racist (and in violation of the rule, "Love your neighbor as yourself").
However, in both of these instances, it could as well be argued that these are the result of personal experience and development: for instance alcoholism is seldom found in infants but develops as individuals gain experience of alcohol and see it as a solution to their problems or a route to happiness.
- "Did you not read that He made them at the beginning of creation, male and female, did He not?
- "And it said, because of this a man leaves his father and his mother and clings to his wife and they become both one flesh.
- "From then on they are not two, except one body. What God has thus united, a human being does not separate." (Matt. 19:4-6)