When is obedience to a created being considered apostasy that expels one from the fold of Islam, and when is it considered a sin or an transgression that does not amount to apostasy? And are court clerks and writers considered among those who do not rule by what Allah has revealed, and is their work unlawful?

Obeying a creature in declaring lawful what God has forbidden, or declaring forbidden what God has made lawful, while believing in its validity, is a major disbelief that expels one from the ملت (religious community). However, obeying a creature in sins while believing in their unlawfulness does not expel one from the ملت. Abandoning the judgment by what Allah has revealed and instead judging by man-made laws or pre-Islamic customs is considered major polytheism (shirk akbar) and contradicts Tawhid (monotheism) and the testimony that there is no god but Allah and that Muhammad is the Messenger of Allah, because it undermines the very essence of Tawhid. Whoever obeys other than Allah in declaring lawful what Allah has forbidden, or declaring forbidden what Allah has made lawful, has taken that entity as a lord and a partner, and that contradicts Tawhid.