Creationism

[Belacqua]

So the idea being referred to here isn't that time had a beginning, but rather that it doesn't make sense to talk about "before" the beginning of time. And "first" of course shouldn't necessarily be understood to mean "absolutely first in the history of mankind" but rather first relative to modern "people who say the same about the Big Bang".

It's not at all controversial to point out that Augustine changed the way people think about time.

http://research.iaun.ac.ir/pd/fahim/pdfs...M_6840.pdf

Saint Augustine provides a new and modern interpretation about reality of time. He considers time as an aspect of soul and mind. Contrary to ancient Greek thinkers which imagine the time as a dimension of nature, Augustine considers time as extension of soul present in memory and expectation. [...] But Augustine does not consider time as imagination or personal fantasies. He considers time one dimension of human nature and soul and considers time as mind awareness toward transient and variable matters.

Modern physicists also consider the possibility that time is a result of the way people experience the universe. I have no idea how widely accepted this is among scientists.

This paper:

https://www.ijhssnet.com/journals/Vol_6_...2016/4.pdf

looks at both Confessions and On Genesis and compares Augustine's two analyses of how time works. While one considers time to be objective and the creation of God, the other analyzes the human experience of time. 

The Greeks generally held that time is infinite. Augustine re-opened the discussion in ways that are still being discussed -- for example, the degree to which time is a mind-independent phenomenon vs. how much it is a human experience. It's not unusual to hear that he is the most important philosopher on the subject of time, in that he raised the topics that are still being discussed. 

Augustine develops two accounts of time.
1. Time is a creature of God.
2. Time is a phenomenon of human consciousness.
The first account of time, that is to say, time seen as a creature of God has three characteristics. First, time is not eternal. Second, time is objective in the sense that time does not depend upon human consciousness. Third, time is related but not completely identical to the motions of the heavenly objects. Augustine’s second account of time, that is to say, time seen as a phenomenon of human consciousness, suggests that time is present in the human mind.

The same paper summarizes his view on how it is incoherent to talk about "before" there was time.

Since time had a beginning, the question, “What was God doing before He made heaven and earth?” is meaningless (Augustine 2006, pp. 241-242). The question itself is meaningless because there was no time. Augustine states, “if before heaven and earth were made there was no time, then what is meant by the question, ‘What were You doing then? If there was not any time, there was not any ‘then,” (Augustine 2006, p. 242). The question involves a category mistake. The term “before” and “after” signify relations between occurrences in time. If there is no time, then it would be pointless to talk about what happened before a certain event. We can only talk about “before” and “after” once time has began. This suggests that time, as a creation of God, had a beginning.

It would be interesting to hear that someone before him had suggested similar ideas. I don't happen to know of anyone.