The Ruling on Dividing Innovations into Good and Bad

Question:
What is the difference between a good religious innovation and a bad one? And how do we know each of them?

Answer:
The correct view is that all religious innovations are bad, all of them are misguidance, and there is no such thing as a good religious innovation. The Prophet (peace and blessings be upon him) said: As for the statement of some scholars that it is divided into two categories: good and bad, this is a statement from their own minds, and there is no evidence for it.
The correct view is that there is no good religious innovation; they are all misguidance. What they call "good" is not from the category of religious innovations, but rather it is a matter that the Shari'ah has brought, such as adding diacritical marks to the Qur'an and vocalizing it so that people do not make mistakes in it. This is what Allah has commanded us to do; He commanded us to preserve the Qur'an and to standardize it.
And similarly, establishing schools for study, even though they did not exist in the time of the Prophet (peace and blessings be upon him), were established out of the need for them. Mosques were built in a manner different from the manner of the Prophet (peace and blessings be upon him); the Prophet built it with trunks, and the people built it after him with stone or otherwise, such as what 'Uthman built. There is nothing wrong with this; this is not from the category of religious innovations. This falls under the category of caring for the affairs of the religion and establishing the rites in the best possible way, as much as possible.