What are the detailed criteria for ruling an issue to be an innovation (bid'ah), considering that the means leading to Sunnah and obligatory acts are commanded? And how is the ruling that saying "صدق الله العظيم" (Allah the Almighty has spoken the truth) after recitation is an innovation explained, while some matters not practiced by the Salaf are not considered innovations despite achieving benefits, such as explaining Hadith, authoring comparative jurisprudence, and elaborating on interpretations, even though the Salaf forbade excessive elaboration?

The essence of the answer:

The issues mentioned in the question: Such as the statement of the Salaf regarding the texts of the Attributes, "Pass them on as they came," does not mean prohibiting the explanation of their meaning. Rather, it means refraining from delving into their modality (kayfiyyah). The intention is to affirm the reality of the meanings and believe in them, while negating knowledge of the modality. The compilation of comparative jurisprudence books, extensive exegeses, and other scholarly works is not a reprehensible affectation; rather, it falls under the preservation and regulation of knowledge, the foundations of which began in the era of the Companions. The story of 'Umar with Allah's saying: "{and fruits and herbage}" has no relation to innovation in religion. Rather, it is in the context of warning against speaking about the Qur'an without knowledge, and Ibn 'Abbas clarified the meaning of the verse to 'Umar, and he did not object to him. As for the questioner's request for a complete methodological definition of innovation, the scope of a fatwa does not accommodate it.