“The faithful who have noetic prayer* . . . [that is, those whose heart of their souls has been reopened through purification and llumination, and pray from said heart, the nous] have spiritual priesthood, especially those who have reached such a degree of grace as to pray for the whole world. This is the spiritual liturgy on behalf of the world. The prayers of these people, who sacrifice themselves praying on behalf of all, sustain the world and heal men. Therefore by prayer they become ‘exorcists,’ driving out the demons which rule in human societies. This the great work of those who pray unceasingly for the whole world” (Met. Hierotheos).
*Noetic prayer, prayer from the heart of the soul, is “the mystical liturgy of the nous” – Gregory of Sinai.
Note: The spiritual priesthood referred to above is completely different than the sacramental priesthood; the two are not interchangeable and are not to be confused.