Res divina

In ancient Rome, res divinae, singular res divina (Latin for "divine matters," that is, the service of the gods), were the laws that pertained to the religious duties of the state and its officials. Roman law was divided into the res divina and res publica, the divine and public or political spheres, the latter phrase being the origin of the English word "republic." Res divina also means, as a technical term, ritual sacrifice.

In the Roman system of belief, religio was the acknowledgement of superiors through honores (honours). Caelestes honores ("heavenly honours") were offered to the gods, and very occasionally to mortals whose actions had earned great benefits for mankind. Earthly hierarchies reflected the celestial order.

Cicero, who was both a senator and augur, investigates the nature of res divinae and res humanae (human affairs) in his treatise De natura deorum ("On the nature of the gods"). He makes no attempt to develop an internally consistent system in which the rituals of res divinae might be modified by “higher truths” of doctrine or revelation. He concludes that even if the nature and existence of the gods cannot be proved beyond doubt, it is wise and pragmatic to honour them by piously offering the time-hallowed rites. Rome's continued success might depend on it. Cicero's reasoning offers a stark contrast to later Judaeo-Christian definitions of religion as spiritual and godly in contrast — or opposition — to those things regarded as material and temporal.

Res divina is an example of ancient Roman religious terminology that was taken over and redefined for Christian purposes, in this case by Augustine. In Augustinian usage, res divina is a "divine reality" as represented by a sacrum signum ("sacred sign") such as a sacrament.

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