Is following the madhhabs considered an innovation or a departure from the saved sect? Do the four imams contradict the Qur'an and Sunnah, or are their sayings within the correct methodology? And is it possible for everyone to engage in ijtihad and derive rulings from the Qur'an and Sunnah?

The book mentioned was authored by a Sunni scholar to clarify that it is not obligatory to adhere to a specific madhhab (school of thought), in response to those who compelled some Japanese converts to Islam to adopt a madhhab. Shaykh al-Islam stated that the four Imams did not contradict an authentic hadith. Adhering to the madhahib does not constitute a deviation from the religion, unless an authentic Sunnah is violated due to madhhabi fanaticism, while it is permissible to benefit from an Imam's understanding of texts and his ijtihad (independent reasoning) in matters where there is no explicit text. It is not permissible to follow an ijtihad that contradicts established texts, and it is obligatory to respect the Imams and be keen to follow the truth when they differ.