The Secret Prayer of St. Cyrill

From the Liturgia. My translation:

Creator of all things, visible and invisible, you who governs all things providently ruled, for all are yours, Lord, lover of souls: I bid you, O omnipotent Lord; I am cowardly, lacking virtue, and most worthless of all your servants, while I assent toward your holiest of holies (sancta sanctorum tua) for the purpose of celebrating this holy mystery. Give me, O Lord, your Holy Spirit, the fire devoid of matter (ignem materiae expertem), which is not able to be comprehended in thought (qui cogitatione comprehendi non potest), that consumes all hardness, that burns slanderous inventions (qui duritias omnes consumit), and slays corporeal members, that holds back the movements of the spirit, that impel plentiful imaginations full of passion and sorrow: And even as it is becoming of priests, make me above all mortal thoughts, and give to me pure words, in order that I may perform this proposed offering (oblationem propositam), which is the mystery of all mysteries, in fellowship and communion with your Annointed (Christi tui), to whom glory is due with you, due to the Holy Spirit who restores life (et Spiritui sancto vivificanti), both of whom are of like nature (consubstantiali) at the present, etc.