نظير الأول: بيع الحر، والميتة، والدم
The first category is illustrated by the purported sale of a free human being, carrion or blood.
Under the classical legal treatment discussed here, these are not valid sale subjects for the contemplated transfer of proprietary title. The purported sale therefore does not become the operative legal cause, even if an offer and acceptance have been pronounced.
This differs from a valid sale awaiting a further step such as payment or delivery. Here the subject itself is legally unsuitable. These are historical doctrinal examples, not modern instructions for transacting in persons.