The second chapter distills three distinct understandings of belonging through corporal union. All are based on the biblical principle of “one flesh,” according to which corporal unification of individuals transforms them into a single entity. Two of the approaches developed during the early centuries of the ecclesial tradition, while the third appeared toward the end of the first millennium of the Common Era in Karaite circles. The ecclesial approaches understand the performance of belonging in physical terms as a fixed and irreversible unification, whereas the Karaite approach conceives it in spiritual terms as an elastic phenomenon of shared selfness. Each of the discussed readings of the biblical principle exhibits a different comprehension of the meaning of corporal union and its legal implications.