The "Big Bang" calls to mind several different viewpoints. Let's discuss three very different opinions (not the only ones).
(1) Naturalistic scientists accept the validity of scientific research and discovery which has shown (a) that the Big Bang happened, without question, (b) how it happened, in great detail, and (c) when it happened, with surprising precision. The entire universe began as an infinitesimally small point, has been expanding ever since, and is still expanding. These scientists shrug off any consideration of a possible supernatural component to these astonishing events. To scientists immersed in philosophical naturalism, the events of the Big Bang "just happened," without apparent cause, but with plenty of effect. Atoms and molecules were now present which much later self-organized into complex, unique life forms, including man, according to their belief system. A BEGINNING, however, is a theological concept which troubles naturalists.
(2) Young earth creationists see the Big Bang as an absurd proposal. This event does not fit with their belief in a cosmos and multiple creatures fully formed and created within the last 10,000 years. According to them the great apparent age of the universe, as measured by light billions of years old arriving on earth only now after a journey of billions of light years, is merely an illusion, along with hundreds of other independent evidences signaling earth's enormous age. One writer emailed me wondering why we need such "atheistic science" when God's word is so plain.
(3) Theistic old earth creationists see the Big Bang as God's initial creation event in our realm, bringing time, space, matter, and energy into existence from nothing in one moment of time in the very distant past (13.73 billion years ago). They see a definite change in frame of reference between Genesis 1:1 and Genesis 1:2. Verse 1 speaks of the initial creation event. Verse 2 speaks of conditions on earth's surface roughly nine billion years later. The earth was then ready for additional creative acts such as the sudden appearance of plentiful microbial life followed by additional creation events of new life forms in future eons at widely spaced intervals as conditions became favorable. The fossil record clearly shows this sequence. The very sudden appearance of truly modern man in the middle east sometime in the last 100,000 years was the pinnacle event in the creation sequence. God could have accomplished all of this in one microsecond or in six days. But God is not bound by our time dimensions. He operates both within them and outside them.
Cosmic history beliefs of theistic old earth creationists described in (3) above conform with belief in a supernatural creator, the record of scripture, and the findings of science, but views (1) and (2) do not agree in all three. Let's strive for discernment in such matters, treating those who disagree with love and respect.
