Does following scholarly dispensations lead to apostasy, and is it obligatory to adhere to one jurisprudential school of thought, or is it permissible to adopt the opinions of different schools in various jurisprudential issues?

There are two types of dispensations (rukhsa): legislated dispensations established by the Qur’an and Sunnah, which are recommended to adopt and may sometimes be obligatory; and dispensations of the jurisprudential schools (madhahib), which are a scholar's fatwa permitting something in a matter of disagreement. Following the dispensations of the madhahib absolutely, without a legal basis for preference or without emulating one who is more knowledgeable, but rather out of a pursuit of personal desires, is a reprehensible act and impermissible by consensus. One who does so embodies all evil. However, adopting dispensations and combining rulings from different madhahib through ijtihad (independent reasoning) and preference, or for the layperson to emulate someone they believe to be the most knowledgeable and trustworthy, is permissible and entails no harm.