What is bid'ah, and is every bid'ah blameworthy?

The legal definition of bid‘ah (innovation) is an invented method in religion, intended for worship and drawing closer to Allah Almighty, for which there is no legal basis or evidence from the Quran or Sunnah, and which was not present during the time of the Prophet, peace and blessings be upon him, and his Companions.

The hadith "Whoever institutes a good practice..." and the hadith "Whoever institutes a good sunnah in Islam..." do not mean the permissibility of innovating in religion. Rather, they mean the revival of an existing sunnah, or guiding to it, or acting upon it so that people may follow suit. This is confirmed by the context in which these ahadith were mentioned, as they came in the context of encouraging charity.

There is no such thing as a "good innovation" in Islam, because the Prophet, peace and blessings be upon him, said: "Every innovation is a bid‘ah, and every bid‘ah is misguidance, and every misguidance is in the Fire." Acting upon innovations is rejected and leads to several disadvantages, including accusing religion of being incomplete, implying that the Prophet, peace and blessings be upon him, concealed knowledge, opening the door to personal whims in religion, and abrogating the sunan.