Do the rulings on apostasy apply to a person who was born a Muslim, then apostatized, and returned to Muslim lands as a non-Muslim, or do the rulings on protected non-Muslims (mu'ahid) apply to him?

An apostate is someone who has left Islam for atheism or any other religion. They are treated as an apostate, not as a member of that religion. They are asked to repent (istitaabah); if they do not return to Islam, they are executed. An apostate is not considered a Person of the Book, so their slaughtered meat is not lawful, nor is marriage to an apostate woman lawful. They cannot be a dhimmi, a mu'ahid (one with a treaty), or a musta'min (one granted protection). The punishment for apostasy applies to anyone who commits an act that nullifies Islam, but this punishment can only be carried out by the Caliph or his representative.

An apostate should be invited back to Islam with kindness, reminded of their past in Islam, offered gifts, and assisted with their livelihood in the hope that they might return. A distinction must be made between kind treatment and the Sharia rulings concerning an apostate: an apostate does not inherit nor is inherited from, and their marriage to a Muslim wife is annulled.