Oh, I would assume it’s the redshift, expansion, CMBR, etc. I’m only going by Vilenkin’s statement, “All the evidence we have says that the universe had a beginning.” I would think that would be a correct assumption to make from that statement. Am I wrong?
Here’s a very simple argument that could be filled out more, but more or less does what’s necessary.
If the initial event responsible for the existence of space, time, matter, and energy has a cause, the cause is not physical.
There is a cause of the initial event.
Therefor the cause is not physical.
From there we can conclude that the cause would be without space, time, matter, and energy and would therefore have to exist in a realm that transcends the physical. That realm is what is commonly defined as the realm of the supernatural.