Re-Post: Richard Muller’s Dictionary of Latin and Greek Theological Terms… Mystical Union (uni mystica).
uni mystica (mystical union)
September 30, 2010
unio mystica sive praesentia gratiae tantum: mystical union or union by the presence of grace alone; i.e. a union made possible and maintained by grace rather than by the interrelation of essences or accidents. It goes beyond the uno essentialis (q.v.) of God or, more precisely, the Logos, with all things, since it is the grace and not merely of power and presence. It is, therefore, an unio specialis. Specifically, the term unio mystica, in the orthodox Lutheran and orthodox Reformed dogmatics, refers to the special union, founded on the indwelling grace of God in Christ, that occurs between God and the believer in and through regeneration. The union is mystical because it rests on the mystery of grace and of the unsearchable mercy of God; it can also be called unio spiritualis, spiritual union, since it is not physical or material but of the Spirit. The qualifying phrase, sive praesentia gratiae tantum, is added to the unio mystica in order to mark the difference between this union of believers with God and the hypostatic, or personal, union of the divine and human natures in Christ (unio personalis).
The orthodox therefore define the unio mystica as the spiritual conjunction (coniunctio spiritualis) of the Triune God with the believer in and following justification. It is substantial and graciously effective indwelling. In relation to the ordo salutis (q.v.), or the order of salvation, the Protestant scholastics distinguish the initial unitio (q.v.), or uniting, of the unio mystica, which is the basis for the imputation of Christ’s righteousness to be believer and which corresponds with the adoption (adoptio) of the believer, and the ongoing unio, or union, of the unio mystica, which continues concurrent with sanctification throughout the life of the believer.” (Richard A. Muller, Dictionary of Latin and Greek Theological Terms, Baker, 1985)