Is the prevalence of evil over good a condition for something to be considered an innovation (bid‘ah), and what is the evidence that this necessitates prohibition, and does an innovation whose good outweighs its evil ultimately lead to a greater evil?

Bid'ah (innovation) is an introduced matter in religion for which there is no evidence from the Sharia. It can be either haqiqiyyah (real), meaning it was not legislated at all, or idafiyyah (additional), meaning its origin is legislated, but it has been specified to a time, place, or manner for which no evidence has been provided.

Bid'ah is blameworthy in both its types, for its evil outweighs any good, and its corruption is dominant, even if it entails some incidental benefits. This is because it implies finding fault with the Lawgiver and accusing the religion of incompleteness: "What was not religion then, is not religion today." Thus, the existence of some benefits for bid'ah does not make it legislated, for if its good outweighed its harm, the Sharia would not have neglected it.

Among the evils of bid'ah is that it makes hearts feel self-sufficient through it, neglecting the Sunan and obligatory acts. It leads to a decrease in care for the obligatory acts and Sunan. It can also turn what is known into what is rejected, and what is rejected into what is known. It includes detestable شرعيّ matters and leads to a loosening from the yoke of adherence (to the Sunnah) and a weakening of faith. Furthermore, it involves resemblance to the festivals of the People of the Book.

Likewise, the innovator is defiant of the Sharia and an imitator of the Lawgiver by following his desires, and his heart may be exposed to deviation: "So when they deviated, Allah caused their hearts to deviate."