The justification that homosexuality is wrong and disordered does not have to have a basis in religious doctrine and moral law. One of the first areas of attack used by the LGBT supporters is to single out and attack the doctrine and beliefs of the Catholic Church, but this whole issue of LGBT rights has more depth why it is illogical and disordered in biology and secular reasoning. Using this explanation, it’s much easier to justify why homosexuality is disordered to those who are not Christian and those that are atheist, and show them how Catholic beliefs and doctrine actually correlate with biological law.
Here is the reason why homosexuality is nothing but a condition belonging to a whole classification of disorders of sexual preference, including incest, pedophilia, and zoophylia.
The main purpose and function of sexual expression and sexuality is for procreation. Even my anatomy and physiology lecturer at university stated that “all you young people think that sex was created for fun, but it’s not. Sex was created for procreation. If there was no need for procreation, there would be no need for sex, and it would not exist.”. Males and males can’t naturally procreate, nor can humans procreate with animals. So if natural procreation is not possible between a male and male, or female and female, this makes homosexuality a disorder of sexual preference and an unnatural act. Just like pedophilia and zoophilia are unnatural acts.
Our sexuality was created to be expressed between the male and female genders as they are both biologically compatible with each other and can procreate. This compatibility noted by the differences in the anatomical and physiological characteristics of the male and female bodies. Females produce eggs and males produce sperm which fertilize the eggs. Males and males are not anatomically, physiologically and biologically compatible with each other. Therefore any sexual expression between people of the same gender is disordered and unnatural. Nature has provided the two genders to express sexually between each other. If homosexuality was normal and natural, there would only be one gender.
In reality the only acceptable sexual relationship is between people of opposite genders(male and female), of appropriate age(where procreation is possible and the parents are mature enough to raise a child) and the persons procreating are not related(so no negative effects of inbreeding occur). If all these criteria are met, these all lead to procreation of healthy child and family. This is the way nature intended and not any other way.
Once the definition of what is an appropriate sexual relationship goes outside the boundaries of natural law( how nature intended) and is based on peoples opinion like those used to justify LGBT relationships, than one can justify any form of sexual relationship. Even people in incestuousness relationships have a right to love each other sexually, can be used to justify incestuousness relationships in the future. This is why the definition of what is an appropriate sexual relationship, should only ever be based on biological law and never on opinion as opinions change, biological law does not.
5)LGBT demand for the right to marry. How can LGBT demand rights that never existed in the first place. It’s like a man demanding the right to get pregnant. Both go against natural law. It’s like demanding the right to marry your dog. Marriage is an expression of natural law in our human society, so it can’t include disordered sexual relationships which are not natural.