Perichoresis (Mutual Indwelling)

Each Person of the Trinity dwells wholly in the others without mixture and without ceasing to be Himself. St John of Damascus gives the word its settled theological use: the three have their being in one another, so that where one is all three are, and the works of God outside Himself are never divided between them. The same word does a second job in Christology, where the two natures of Christ interpenetrate without confusion, which is how the Church can say that God was crucified and that a man is worshipped while refusing both the mixture of Eutyches and the division of Nestorius.