I dont think you can compare the Big Bang to “faith” and “belief”. It’s pretty well proven, at least down to 10^-42 seconds of it. It’s only that first Planck Time where the conditions were so extreme and all forces and energy and time were unified that we cannot extrapolate, and thus we call it the “singularity” where our understood laws of physics break down.

There is a lot of proof for the Big Bang. From the Cosmic Microwave Background radiation to the red shift of distant galaxies. We can measure the expansion and (since space and time are intricately woven) we can see the intense energy signature cooled down to mere radio frequencies.

It’s natural to wonder and question, and I’m sure as we (humanity) have a greater understanding of the quantum nature of gravity we’ll understand even more of the Big Bang. But just because we don’t know that initial fraction of a fraction of a fraction…. of a fraction of a second, that doesn’t invalidate all we do know.

In summary, it’s not belief. It’s observable and measurable and consistent with the laws of physics we know all the way to the singularity.

As an example (by analogy) we don’t know what goes in at the singularity of a black hole (where conditions also are so extreme that our current laws of physics cannot describe it) but we know they exist. We’ve even (recently) imaged our own. Not to mention observing their lensing. They are unquestionably real. And even though we don’t know what goes on at the infinitesimal point (or 1D line of a rotating black hole) called the “singularity”, they still exist and are provable and observable.

It’s not a question of “believing” in black holes while admitting there’s still more to learn.

It’s not a question of “believing” in the Big Bang while admitting there’s still more to learn.

P.S. yes, our universe as we know it began at the Big Bang 13.8B years ago. Time and 3D space, space-time, were unified (along with all the forces) so that is why there is no concept of a “before” that moment. However you wish to philosophize about it — some speculate multiverses and others turtles upon turtles 🐢 — it doesn’t matter because that was beyond our 4 dimensional space-time reality.