Such a "first cause", as we argued very early on, would be a timeless entity and therefore a changeless entity. What that entails is that all of that "first cause" happened in an instant that took no time. Which further implies that "... on the first day I, your deity, created this... on the second day, that..." - based religions cannot be compatible with the First Cause argument.
This premise neglects the definition of eternal as outside time. In this definition of eternal, "instant," "time," "no time," "some time," etc. are nonsensical.
would be a timeless entity
More precisely: eternal.
What that entails is that all of that "first cause" happened in an instant that took no time.
This premise neglects the definition of eternal as outside time. In this definition of eternal, "instant," "time," "no time," "some time," etc. are nonsensical.
[Judeo-Christian] based religions cannot be compatible with the First Cause argument.
They're not proven in your argument as incompatible.
As I've said earlier, the first cause argument is often objected to as a "proof for God" because it does not describe in full the Christian concept of God. I agree that it does not.
The rebuttal is that the attributes of eternal, uncaused, unmoved, unchanging, etc. are an integral part of Christian theology and therefore compatible.
I'm avoiding a religious discussion here and sticking to the non-transcendent observation and logic of the first cause argument.
How this would work as far as your objection would be: The first cause, uncaused, eternal, causes the dependent causes finite, in time.
And these, in time, happen in time, and time has days, etc.
So, it could be this is an explanation for that portion.
However, I'm not defending any particular religion biblical stance or interpretation here, rather trying here to stick to the first cause argument. In this context, it doesn't matter to me what the ramifications of the first cause arguments are outside the narrow structure of the argument itself.