The Quranic Parallel To Deuteronomy 4:2

One of the most important verses in the entire Bible is Deuteronomy 4:2, which is so inescapably central in finding the Bible's direct affirmation that the ongoing commands of God are inflexible, and that nothing beyond what he condemns is evil and that nothing he does not prescribe is obligatory.  The commands of God, within Christianity, are the way these obligations are expressed to humans, and though there are logically necessary ramifications of some commands that apply to things not mentioned in the text (such as alcohol abuse being condemned logically necessitating that the same would be true of drug abuse), things that are not condemned by name or by logical extension are not sinful in Christianity.

Thinking that something is evil that is not contrary to God's nature or that something is good that does not correspond to God's nature is the heresy of legalism, which misrepresents the character of the Christian deity and the moral obligations grounded in him within this philosophy.  Legalism is not something only idiotic Christians believe in and practice, though.  Like the ancient (and modern) ideological Jews who so often believe that moral ideas and traditions beyond or contrary to the Torah are prescribed in the text, and like the Christians who let evangelicalism or Catholicism poison them with delusions, many Muslims believe that Islam entails commands that it does not or that it condemns certain things that it does not.

The Quran even has its own version of Deuteronomy 4:2, though on Islam, the Torah is already supposed to be valid, even though the Quranic criminal punishments very sharply contradict those of the Torah.  "'Do not add to my commands or subtract from them,'" says Deuteronomy 4:2.  "Do not say falsely, 'This is lawful and that is forbidden,' inventing a lie about God," says Surah 16:116.  The philosophical overlap is obvious upon reading or recalling both!  Christianity and Islam are very overtly theonomist in their moral epistemologies and overall frameworks, and this is another similarity that is rooted in how it is not human traditions, personal convenience, or subjective conscience that make something good or evil or reveal which, if either, it is.  Legalism is antithetical to Islam as well as Christianity.

What might be some examples of the legalistic things either commonly assumed to be condemned in the Quran (by people who have not read it) or even assumed to be sinful within Islam by Muslims who confuse various cultural or legalistic traditions with Quranic/Allah's commands?  As is the case with Christianity and Biblical ethics, nothing in the Quran actually prohibits the likes of profanity, bikinis, opposite gender friendships, video games, metal music, and so on, yet plenty of Muslims, almost inevitably the conservative kind, think it is the other way around, that they are evil.  Since they join evangelicals in embracing tradition and conscience as either of them has any epistemological validity, they ironically end up betraying the actual philosophical ideas of the Quran by ignoring Surah 16:116.

It is not that Islam is true or even logically possible except in isolated parts, for the Quran conflicts with the very Torah on moral matters of justice, and crucial issues of just punishment at that, all as it states it is the revelation of the same God who provided Mosaic Law to the Israelites.  This disparity means Islam is false whether or not the Torah is true.  None of this is affected by how many things condemned by Muslims or assumed to be condemned by the Quran are not actually prohibited by it.  One of the most significant parts of Islamic legalism is instead the fact that Islam's genuine similarities to Christianity are sometimes distorted by Muslims in the same way actual Christian morality, rather than the moral feelings and traditions most Christians submit to, is commonly distorted by Christians.  Another ramification is that even the opponents of Islam as a philosophical system of theology and ethics might often be misunderstanding how Muslims believing, saying, or practicing something does not make it a component of Islam.