Merry Christmas, Jim Baur!
In his, , 7:28
The Literal Meaning of Genesis: An Unfinished Book, Augustine quotes from Sirach 18:1, “He Who lives forever created all things
simultaneously” (Latin: “
Qui manet in aeternum creavit omnia simul”), and this understanding of this verse becomes one of his interpretive keys to Genesis 1. Likewise, in, , Bk. 5, 3:6
On the Literal Meaning of Genesis, he quotes from this verse in Sirach again as he is working out the meaning of Genesis 2:4.
Augustine understands “the
day that the LORD God made the earth and the heavens” of 2:4 to be the
only “day,” and to be repeated over the course of the six “days” of Genesis 1. After quoting Genesis 2:4, he says, “[n]ow surely gains more influence the view that God created a single day, from which six or seven days could be enumerated because of the repetition of that single day” (Bk. 5, 1:1). In Book 4, 33:52 of the same work he suggests that the Scriptures break down the simultaneity of creation over the course of a six day narrative in consideration of our slowness of mind, to bring us to comprehend this unspeakable event over the course of manageable steps.
However, in Book 6 (see 5:7 and 6:10) he explains that the events taking place in Genesis 2 – the planting of the garden, the naming of the animals, etc. – do not belong to the creative activity described in the six days of Genesis 1 because, in the second narration, the events described require a passage of time. And so he refers these things to the Father’s work that continues even to this day (cf. John 5:17), and he understands the double narratives of overlapping subjects (such as the creation of male and female on the sixth day of Chapter 1, and then again at the planting of the garden in Chapter 2) to be indicators that the things created during the primordial “days” of Genesis 1 were created in some way in
potentiality and
causality. And during the normal course of history narrated in Genesis 2, this created potential unfolds into a greater
actuality. However, in dividing things in this way, it must be appreciated that the seed-like reality of everything that exists, existed from the first moment of creation.
So the answer to your question about why Augustine understood creation as being all at once is, for the most part, Genesis 2:4 and Sirach 18:1. He seems to have supplied additional reasons, such as
(1) the relationship that exists between the creative “words” of Genesis 1 and the Eternal Creator-Word, and
(2) the fact that the first day of creation is not referred to as the “
first day,” but as “
one day” (Genesis 1:5); but I am afraid to elaborate on them here lest I misrepresent Augustine even more than I may have already done. My warning to you is that I am working with languages that I do not know, and with works of Augustine that I have not read in their entirety. If I am wrong even in what I have presented here, I am sorry to have misled anyone and to have misrepresented this great Saint, and I hope that someone will come behind me and correct my errors.
May the LORD be with you!
Pete