Oak OAN (Oracles Against the Nations)
Obadiah Oberammergau Passion Play Occam's Razor Octavian Odes of Solomon

Oecolampadius, John Og

Old Testament Olive - Olive Oil Olivet Discourse OMF - Overseas Missionary Fellowship Omnipotence Omnipresence Omniscience
On Onan One Kind, Communion in _ Onesimus Onesiphorus Onomotopoeia Onqelos Ontology Ontological Argument

Open Theism Opera ad intra - Opera ad extra Ophel Ophir Optative Order of Preachers (OP) Ordo Salutis Organistic Philosophy Ordinal Origen Original Sin Orion Ostracon - Ostraca Ossuary Ottoman