In this volume, Bradley R. Trick argues that Hellenistic testamentary adoption provides the key to understanding Abrahamic descent and its implications for the law in Galatians. By thoroughly analyzing the Greco-Roman and Jewish contexts of Paul’s references to testaments/covenants (διαθῆκαι) and adoption, Trick establishes that Gal 3-4 portrays the Abrahamic διαθήκη as a Hellenistic testament through which God adopts Abraham. This insight enables a coherent and collectively consistent interpretation of Paul’s Abrahamic appeals to emerge, one in which “sons” (3:7) designates Jews, “children of promise” (4:28) designates gentiles, and “seed” designates Christ (3:16) and the interdependent union of Jews and gentiles in Christ (3:29). The need to preserve the singularity of this seed then grounds God’s giving of the law.