homosexuality, masterbation, pre-marital sex, sado-maso and other "filthy" sexual acts?
What reasons do the 3 major religious books (Talmud, Qu'ran, Bibble) give that make homosexuality, masterbation, pre-marital sex such bad things?
Keep it intelligent plz.
Let's address each topic individually:
Homosexuality
The Qur'an states that it is normal for some people to have homosexual thoughts and be moved by the beauty of a person of the same sex. What a person should not do is act on these urges and fantasies.
Again, it's like any other forbidden thing in Islam, adultery, consumption of alcohol, gambling. It's not seen the same way in the Qur'an that it's seen by Christians (ie: the thoughts are permissible but carrying them out is not), although some Muslims may still be made very uncomfortable by the topic.
In regards to punishment, a homosexual act is treated the same way that adultery is treated, since one cannot be married to a person of the same sex (and therefore to do such a thing must be unfaithful to his wife or to engage in sexual intercourse while unmarried, also prohibited).
If two men for instance want to be together, and they express their affection for one another in private, as to not encourage such action (and therefore disobedience) among other members of the Muslim community, then they can do that.
The only way to be punished for homosexual behaviour is the same way one would be punished for adultery. There's deliberately a very high standard of proof set. One needs to be caught in the act by several people that can corroborate each other's testimonies, so you need several witnesses
of the act itself.
Furthermore, there's nothing (that I've read) to say that a homosexual (one that engages in the act) is incapable of making it to paradise (and is doomed to hell). The Islamic understanding of judgement is that your good deeds and your bad deeds (including being disobedient) are compared when you stand "before God." Based upon these deeds, it is decided whether a person deserves to enter Paradise. God knows that no one is perfect, and it is within his power to forgive anyone he wants to, which is why he's called Ever-Merciful, Most-Compassionate and Most-Forgiving.
I even read somewhere (though I can't recall where) that in paradise, people will have access to both men and women partners (if they choose). Also, I recall that people will be able to drink wine (therefore, the prohibition on alcohol is also lifted).
Islam and this "current life" is considered by Muslims to be a trial from God to test their piety, commitment and willingness to submit to God and his laws. Therefore, once in paradise, there's no longer a need to be tested, since you've clearly passed the test.
Adultery
From Wikipedia (accurate and concise description with references): According to Islam, adultery is a violation of a marital contract and one of the major sins. In Islam, adultery includes both pre-marital and extramarital sex. Fornication and adultery are both included in the Arabic word 'Zina'. As they belong primarily to the same category of crimes, entail the same social implications and have the same effects on the spiritual personality of a human being, both, in principle, have been given the same status by the Qur'an.
"Do not go near to adultery. Surely it is a shameful deed and evil, opening roads (to other evils)" (Quran 17:32).
"Say, 'Verily, my Lord has prohibited the shameful deeds, be it open or secret, sins and trespasses against the truth and reason"' (Quran 7:33).
"Women impure are for men impure, and men impure are for women impure and women of purity are for men of purity, and men of purity are for women of purity." (Quran 24:26)
Conditions (apply also to homosexual acts, since they are considered a form of adultery)
* The accused, before the accusation, must be known as a practising Muslim.
* The accused must possess common sense. The accused must not have been in an intoxicated state of mind while the act was committed.
* The accused must be an adult having well surpassed the age of puberty.
* The accused must have committed adultery of his/her own free will.
* There must be four male witnesses (or pieces of evidence) to support the accusation (of sexual penetration).
Additional fulfillment of the following requirements is necessary for an execution:
* The accused must be free and not a slave.
* The accused must be married (according to Islamic Law), and must enjoy normal sexual relations with his/her spouse (and therefore have a legitimate means of satisfying his/her sexual desires) prior to committing adultery.
* The accused (woman) must not be pregnant or be responsible for breast feeding a child.
The penalties for adultery (depending for instance if one is fornicating - ie: unmarried or does have a wife) include physical punishment, such as 100 lashes or possibly the penalty of death.
However, recall that there are a number of conditions that need to be met, that four witnesses are required, and each must corroborate the others' testimony and evidence such as Hearsay is inadmissible.
Masturbation
Also from Wikipedia: Istimna (استمناء
is the Arabic term for masturbation. Masturbation may only be done in fear of committing adultery, nor is it preferred (either getting married and fasting is suggested as alternatives from hadith). It is totally forbidden in the Shi'a sect[citation needed], but the four Sunni schools of jurisprudence (known as Madhaahib - the Hanafi, Shafi'i, Maliki and Hambali schools of Fiqh) have differing stances on the issue[citation needed]. Some consider it forbidden in all cases[citation needed]. Some see it forbidden in certain cases but obligatory in others[citation needed]. Another view [attribution needed] is that it is Makruh but not expressly forbidden. Scholars of Islam do not approve of masturbation, except in extenuating circumstances. There is a statement in Quran "And those who guard their chastity, Except in the case of their wives or those whom their right hands possess,- for then, they are free from blame; But whoever seeks beyond that, then those are transgressors."
In Islam, sexual engagement outside of marriage (and outside of those whom the right-hand possesses) is a major sin, which cause the doer to be punished in this life and the Qiyama. Yet if one's desire is so overwhelming one might perform a greater wrong by having sex outside marriage, masturbation becomes permissible as a necessity but in that case it will be like eating the flesh of pig when no other food is available. So Quran says "And those who are not married should try to live in chastity, until God enriches them with His Grace" (Qur'an, 24:33)
Beliefs and practices vary, it is not, however, in any case a sin for which there is a prescribed punishment.
Sodomy
I'm not completely sure what other "dirty" sexual acts you're talking about, but I'm assuming your interested in at least sodomy.
Islam is a religion that places a high emphasis on cleanliness and hygiene. I'm not sure how much you or others know about the religion, but before every prayer, a person makes "Wudu" which is a spiritual act of purification. This involves washing the body to cleanse it before prayer (particularly the hands, arms up to the elbows, feet, nostrils, ears, face, and hair). Also if a man discharges semen, or a woman has her period, they have to undertake a more thorough cleaning of themselves (ie: like a bath/shower).
Therefore, the act of sodomy runs completely contrary to these values. It is officially prohibited by most Islamic sects (most importantly, the largest ones representing the vast majority of Muslims). Parts of the Qur'an talk about Sodom and Gomorrah as well as the sin of Lot's people.
People who do this are seen to be giving in to a universal temptation (such as thievery) and are punished accordingly. It is distinguished however whether a person makes "lesser liwat" with a woman or "greater liwat" with a man.
The punishment can be severe, including whiplashes or death.
Recall however, that like adultery, the burden of proof is high.
Regarding all of the acts described above (aside from masturbation), they are made difficult to prosecute and prove (possibly intentionally). In my opinion, this is because committing these acts privately does not have the same impact as committing them while the Muslim community is aware. In other words, if people know that such transgressions are occurring, they may be more likely to transgress themselves, and this is the key problem when such behaviour occurs and is prosecutable.
Even if such action can not be prosecuted, that does not mean that it isn't wrong. Recall that the Islamic notion of God, much like the Christian and Jewish notion is that he is "All-Aware" and therefore will know if a person exceeded the limits set in the Qur'an. It's like a person who steals and isn't caught. They may not have been found guilty of a crime, yet a crime was committed nonetheless.
It should also be noted that many of the things that are prohibited in the Qur'an are done so because
their benefits are outweighed by their costs. Examples of such things are alcohol consumption, gambling and so on. Consider alcohol consumption. Some studies show that a very small amount of alcohol may have certain minor health benefits (though the majority of doctors would still caution a person against drinking solely for the gain of these potential benefits). Despite this, it is very uncommon for a person to consume alcohol purely for these "good reasons." Instead, we see widespread alcohol abuse problems, drunk driving, and even casual drinkers consuming far more than this "minimum" alcohol amount.
Furthermore, when it comes to gambling, it may be possible to earn a fortune through it. On the other hand, it's equally possible (or more likely in many cases) that a person will lose money by gambling (how else would casinos remain profitable

?) Therefore, people could gamble their livelihoods away, which has sometimes been the case and go from a position of affluence and wealth (or at least a reasonable amount that provides a good home and meets the needs of the family) to a position of shocking poverty.
I hope this was helpful for anyone curious about the Islamic point of view.