Is 'forbidding the halal and allowing the haram' in Islam considered shirk?

Question

Can you provide hadith and Quran verses to support your answer. A lot of people say it is but I have only seen 1 verse in the Quran about it:

اتَّخَذُوا أَحْبَارَهُمْ وَرُهْبَانَهُمْ أَرْبَاباً مِنْ دُونِ اللَّهِ وَالْمَسِيحَ ابْنَ مَرْيَمَ وَمَا أُمِرُوا إِلاَّ لِيَعْبُدُوا إِلَهاً وَاحِداً لا إِلَهَ إِلاَّ هُوَ سُبْحَانَهُ عَمَّا يُشْرِكُونَ

“They (Jews & Christians) took their rabbis and monks to be their lords besides Allah (by obeying them in things they made lawful or unlawful according to their own desires without being ordered by Allah), and Messiah, son of Maryam, while they were commanded to worship none but One Ilah – La ilaha illa Huwa – Praise & glory be to Him from having the partners they associate (with Him).” (Quran 9:31)

But there's no direct ruling to Muslims saying that doing it would be shirk. What if you know the halal and Haram in Islam and follow it, but you see other Muslims do sin, and don't know/deny it's a sin and not tell them it's a sin. Is that considered shirk? What if you know the Muslims are stubborn and won't listen to you as well?

Answer 1

             In the name of Allah, the most compassionate, the most merciful

Based on my research, it mustn’t be considered as Shirk, since the definition of Shirk is something else.

Since according to the definition of Shirk:

Literally, shirk means to allocate; technically, in Quranic terminology, shirk – in contrast to hanif – signifies the process of allocating someone/thing as the Almighty Allah’s partner or equal. Hanif means being inclined towards righteousness and moderation; hence, the term has been coined onto those who have disassociated themselves from shirk, abiding by pure tawhid.

Therefore we cannot call it Shirk.

You’d better see the source before as the complete definition of Shirk.

---

Source: www.islamquest.net (in English)

Answer 2

I think you meant forbidding the halal I don't know if it's considered sherk or not but the Quran says:

قل من حرم زينة الله التي أخرج لعباده والطيبات من الرزق قل هي للذين آمنوا في الحياة الدنيا خالصة يوم القيامة كذلك نفصل الآيات لقوم يعلمون -سورة الأعراف

Say, "Who has forbidden the adornment of Allah which He has produced for His servants and the good [lawful] things of provision?" Say, "They are for those who believe during the worldly life [but] exclusively for them on the Day of Resurrection." Thus do We detail the verses for a people who know.

and also

ولا تقولوا لما تصف ألسنتكم الكذب هذا حلال وهذا حرام لتفتروا على الله الكذب إن الذين يفترون على الله الكذب لا يفلحون --سورة النحل

And do not say about what your tongues assert of untruth, "This is lawful and this is unlawful," to invent falsehood about Allah. Indeed, those who invent falsehood about Allah will not succeed.

So it's mentioned in the Quran that you should not do this.