Thesis advisor: Pheme Perkins / Psalm 110:1 was not a Second Temple messianic proof-text. Yet, it became the early Christian text par excellence for articulating exaltation Christology: Jesus was exalted to God’s right hand (Acts 2:33, 34-35; 5:31; 7:55-56; Rom 8:34; Col 3:1; Eph 1:20; 1 Pet 3:22; Heb 1:3, 13; 8:1; 10:12; 12:2) and κύριος of the cosmos (Phil 2:9-11). Therefore, this unprecedented and singular use of Ps 110:1 by early Christians requires an explanation. This dissertation argues that the unparalleled Christian use of Ps 110:1 is indebted to a Greco-Roman royal ideological concept: rulers as sharers of divine/sacred space, which consisted of three elements: temple sharing, throne sharing, and joint temples of imperials and gods. Greek cities and Roman period provinces made autocrats sharers of sacred space to show appreciation for concrete royal benefactions and to acknowledge the piety of monarchs and divine approval of their regimes. Early Christians adopted two of these practices—temple sharing and throne sharing—for similar purposes, creating a unique variant of the Greco-Roman royal practice and using scripture to justify it (Ps 110:1). Consequently, early Christian use of Ps 110:1, exaltation Christology, and Jesus’s Lordship are indebted to royal messianism. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Theology.