One of the intriguing threads in Knight is his rehabilitation of biology within theology - or, more specifically, the inclusion of “blood and seed, of sonship and messiah, of holiness and purity” within pneumatology. Contesting the common opposition of fictive and biological kinship, he says that “we should understand ‘fictive’ as a synonym for ‘adoptive,’ ‘elective.’ A household head can adopt a son, say by raising a freed slave to this status, and this elective kinship will be cemented by marriage and the arrival of heir biologically related to both parties. On this basis fictive kinship means only kin elect, the source of future kin. Elective relationship, relationships ‘by faith,’ are in the long run constitutive of biological relationships.”