“For it was fitting for the Creator of the universe, who by the economy of His incarnation became what by nature He was not, to preserve without change both what He himself was by nature and what He became in His incarnation.
For naturally we must not consider any change at all in God, nor conceive any movement in Him. Being changed properly pertains to movable creatures.
This is the great and hidden mystery, at once the blessed end for which all things are ordained. It is the divine purpose conceived before the beginning of created beings.
In defining it we would say that this mystery is the preconceived goal for which everything exists, but which itself exists on account of nothing.
With a clear view to this end, God created the essences of created beings, and such is, properly speaking, the terminus of His providence and of the things under His providential care.
Inasmuch as it leads to God, it is the recapitulation of the things He has created. It is the mystery which circumscribes all the ages, and which reveals the grand plan of God (Eph. 1:10–11), a super-infinite plan infinitely preexisting the ages.
The Logos, by essence God, became a messenger of this plan (Isa. 9:6) when He became a man and, if I may rightly say so, established Himself as the innermost depth of the Father’s goodness while also displaying in Himself the very goal for which His creatures manifestly received the beginning of their existence.”
–Maximus the Confessor, Ad Thalassium 60, in On the Cosmic Mystery of Jesus Christ: Selected Writings from St Maximus the Confessor, ed. John Behr, trans. Paul M. Blowers and Robert Louis Wilken, vol. 25, Popular Patristics Series (Crestwood, NY: St Vladimir’s Seminary Press, 2003), 124–125.