By Metropolitan Hierotheos of Nafpaktos
Christ's sacrifice on the Cross at Golgotha, which is closely linked to the Resurrection of Christ, is the central point in the teaching and life of the Church. And we also speak of the mystery of the Cross and Resurrection of Christ in regards to the victory of Christ over sin, the devil and death.
There is a distinction between "the bodily Crucifixion and Resurrection of the incarnate Word of God" and "the mystery of the power of the Cross and the Resurrection of Christ, witnesses of which were the Prophets and some Apostles before the sacrifice on the Cross at Golgotha." Despite this distinction, there is a close relationship between the mystery of the Cross and the sacrifice of Christ on the Cross at Golgotha.
Venerable Isaac the Syrian, speaking of the Cross of Christ, writes that "the work of the Cross was two-fold". The first action of the Cross is called "praxis" and is experienced as patience during trials of the flesh, and expressed in the spirited part of the soul. The other action is called "theoria" and consists in the refinement work of the nous, and is found in divine contemplation and in the occupation of prayer which is contributed by the appetitive part of the soul. So, the Cross is praxis and theoria.
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The Cross of God is His love, which is His uncreated energy.
"The power of the Cross and the Resurrection is the love of God 'which was before the cosmos', as well as during the creation and establishment of the world; before the incarnation, and during the incarnation; before the sacrifice on the Cross, and during the sacrifice on the Cross, as well as after." (Fr. John Romanides)
Source: Ekklesiastiki Paremvasi, "Τό μυστήριο τού Σταυρού καί τής Αναστάσεως τού Χριστού", April 2012. From Empirical Dogmatics According to the Spoken Teaching of Father John Romanides, vol. 2. Translated by John Sanidopoulos.