This article investigates the semantics of the protasis of the manumission law of the Covenant Code (Exod. xxi 2a). Despite the proposal by John Van Seters that the slave there purchased must "already" have been a slave, such a restriction of meaning goes beyond the evidence. Critical for understanding the semantic issue is the overlooked distinction between two types of verbal object: "affected" and "effected" objects. Moreover, verbs of creation and appointment are frequently ditransitive. Such verbs may also leave the affected object implicit while specifying only the effected object. This construction emphasizes the change in status undergone by the grammatical patient, as in the case of the manumission law. Attention to the contractual language of biblical law permits, in turn, a more adequate concept of the grammatical concept of effected object.