Interesting thread. So many who think morality is something they can decide for themselves. I'm sorry, but that is only opinion, not morality. The very existence of morality -- regardless for the moment of what you may feel is or is not moral -- indicates it is imposed upon us from outside the human race. If you look above, you will find many arguments as to what is or is not moral, but no arguments about the fact that morality exists.
It not only exists, it is something we all appeal to as something objective -- outside of ourselves.
It is WHAT is moral or immoral that we fight about, not whether morality exists. And that is a telling point. If we know morality exists, and we do, we really ought to look at where it comes from.
And, Christian or not, religious or not, there is no other option than that morality is imposed upon us by our Creator and that He has defined what is moral and what is not.
Pornography in any form is immoral. Enjoyment of it is no criteria, by the way. Immoral behavior can often be quite enjoyable in the short term, or it wouldn't have so many defenders!
But pornography is immoral because it does not keep the marriage bed holy. "Marriage should be honored by all, and the marriage bed kept pure, for God will judge the adulterer and all the sexually immoral." Hebrews 13:4
Pornography is the devil's tool. Let me explain that one, please.
In the Old Testament, we find a number of 'pictures' of spiritual truths. Egypt is considered a 'type' for sin. Moses and Joseph both are considered 'types' of Christ. The Promised Land is a 'type' of the New Creation, etc. Jesus Himself used many pictures of commonly known items, such as weeds, seeds, pearls, trees to explain spiritual truths. I think you will find, if you look, that everything in the physical world is actually some kind of limited picture of a spiritual truth.
When a person asks Jesus to take over his or her life, to 'come into my heart' or whatever phrase is used, then the person becomes born again and is indwelt by the Holy Spirit: "And if anyone does not have the Spirit of Christ, he does not belong to Christ." (Romans 8:9)
There is only one physical picture of what happens when a person accept Christ as Lord and Savior -- and that is sex. Christ comes into a person's life and a new life is born in that person. Thus, sex may be seen as one of the holiest pictures God has given us. It is something to be cherished within the marriage relationship. Paul defines the church as Christ's bride, so we again have the indication of a very intimate relationship being pictured.
With only this picture to help explain a spiritual truth of supreme importance, no wonder Satan will do everything in his power and imagination to distort it. Whether it is the homosexual life, pornography, adultery, fornication, or any other form of sex which is not within the marriage relationship -- whether 'consensual' or not makes no difference -- it is immoral. "Thou shalt not commit adultery" covers every sexual relationship outside of marriage. And Jesus warned that simply looking at a woman with lust was adulterous. Pornography is nothing if not encouraging folks to look at others with lust!
It involves images you can never remove from your mind. It is a permanent stain in your brain unless God Himself miraculously removes it, which He can do and has done for some.
But make no mistake -- pornography is directly and specificially in rebellion against God and His commands -- which, by the way, were given to us for our own good.