To introduce a change in these doctrines even at the level of questioning with bad intention is considered as Bid’ah, i.e. innovation that is fiction, fabrication. No change can be introduced in the order of prayer, the time of breaking the Ramadan fasting, the pillars of Islam, and a thousand others that are recorded in the Quran. Prohibitions and permitted things cannot be changed either. It is permissible to argue in order to deduce the reason of the prohibitions, but whatever the outcome of the explanation is, it is not possible to change the prohibitions, concessions and regulations.

It was narrated that Jabir bin 'Abdullah said: "In his Khutbah the Messenger of Allah (peace be upon him) used to praise Allah as He deserves to be praised, then he would say: 'Whomsoever Allah (SWT) guides, none can lead him astray, and whomsoever Allah sends astray, none can guide. The truest of word is the Book of Allah and best of guidance is the guidance of Muhammad. The worst of things are those that are newly invented; every newly-invented thing is an innovation and every innovation is going astray, and every going astray is in the Fire.' Then he said: 'The Hour and I have been sent like these two.' Whenever he mentioned the Hour, his cheeks would turn red, and he would raise his voice and become angry, as if he were warning of an approaching army and saying: 'An army is coming to attack you in the morning, or in the evening!' (Then he said): 'Whoever leaves behind wealth, it is for his family, and whoever leaves behind a debt or dependents, then these are my responsibility, and I am the most entitled to take care of the believers.'"
Grade: Sahih, Authentic
Reference: Sunan an-Nasa'i 1578

Bid’ah does not mean the rejection of religious debates and in such debates the questioners and petitioners cannot be considered without any basis as Mubtad’ah, i.e. the petitioner of fabrication. After all, the thinking with good intention in the practice of faith is Ijtihad, i.e. pursuit for improvement. While bid’ah is a serious sin, no one can throw that blame to anyone without debate or reflection, as it is not ruled out that a suggestion is not based on “fictional renewal” but on simple goodwill.

Bidʿah, in Islam, any innovation that has no roots in the traditional practice (Sunnah) of the Muslim community. The most fundamentalist legal school in Islam, the Ḥanbali school (and its modern descendant, the Wahabiyah sect of Saudi Arabia) rejected bidʿah completely, arguing that the duty of a Muslim was to follow the example set by the Prophet (Sunnah) and not try to improve on it.

Most Muslims, however, agreed that it was impossible to adapt to changing conditions without introducing some types of innovations. As a safeguard against any excesses, bidʿahs were classified as good (ḥasan) or praiseworthy (maḥmudah), or bad (sayyʾah) or blameworthy (madhmumah). They were further grouped under the five categories of Muslim law as follows:

1. among bidʿahs required of the Muslim community (farḍ kifayah) are the study of Arabic grammar and philology as tools for the proper understanding of the Qurʾān, evaluation of Hadith (traditions or sayings of the Prophet Muhammad) to determine their validity, the refutation of heretics, and the codification of law;
2. strictly forbidden (muḥarramah) are bidʿahs that undermine the principles of orthodoxy and thus constitute unbelief (kufr);
3. recommended (mandub) is the founding of schools and religious houses;
4. disapproved (makruh) are the ornamentation of mosques and the decoration of the Qurʾān; and finally
5. the law is indifferent (mubaḥah) to the bidʿahs of fine clothing and good food if those follow the rules of Islam.

The accusation of bid'ah cannot be established without associating partner to God. In order to produce an innovation, fabrication, one needs to have a tendency, a reason, a motivation that makes one want to appear in a supreme, a Divine height. So Bid’ah and Shirk (i.e. associating partner) go together.
As always, the American super productions are the best examples for demonstrating bid’ah, too. Dramaturg: “It happened a hundred years ago! Right in the middle of the desert, in a place where man cannot live among the bleak stones, where the heat dries up all trace of life, a hero suddenly appeared. This hero, in defiance of challenges, the plagues of nature, brought the life-giving word of God to men (so far is shirk, i.e. associating partner to God and hence the bid’ah). Follow me, he said, then raised his hand to the sky and said: God has a message through me that you should not follow Muhammad but me and prayer is not obligatory…and from now the bid’ah starts.” It was only an example!
This is what the relevant verse of the Quran is about:

What! have they partners (in godhead), who have established for them some religion without the permission of Allah. Had it not been for the Decree of Judgment, the matter would have been decided between them (at once). But verily the Wrong- doers will have a grievous Penalty. (Quran 42:21)

Nothing can exist without the permission of Allah. Can people, who indulge in false worship say: "Why does Allah permit it?"