Genesis Story.
Big Bang.
Both accounts are consistent in one thing: universe is of finite age. There are other creation myths. I confine myself to Genesis merely because I am most familiar with it, and desire to write a pithy blog post, not a treatise.
Is a belief in a universe of finite age theologically or cosmologically necessary? Perhaps not. First the cosmology, then the theology. With references to my earlier posts on non-eternities and on different types of eternities. All of this is the work of an amateur. Read and consider at your own risk.
Entropy and Eternity
If there is some quantity in the universe, for example, entropy, that always increases as time flows, then we can infer that this rule of increase cannot always have been true from time eternal. This is a consequence of the second law of thermodynamics. If, for example, entropy has been increasing forever, then the present entropy of the universe must be infinite. Entropy cannot be infinite, because the universe has order. Therefore either eternity without Beginning exists and entropy does not always increase with time, or eternity without Beginning does not exist.
If the 2nd Law is not universally true, we may be in a linear or circular non-eternity. Due to the ultimate impossibility of distinguishing between linear and circular non-eternities, and if we are in one or the other, we cannot know which of these situations we are in. Another possibility, if the 2nd Law is not universally true, is that we exist in an open-ended linear or spiral eternity.
If the 2nd Law is universally true, we may be in a one-ended linear eternity with a rather bleak future. In that case, entropy will continue to increase until it reaches a state in which no further disorder is possible. A state of maximum disorder is not changeless in one sense, and yet is changeless in another. Maximum disorder is that state of a system, of which it can safely be assumed that all subsequent change is forever random. So its state of disorder never changes; it is changeless in one sense by remaining forever random. Yet is is always changing. On the other hand, it may be impossible for the universe to obtain perfect (infinite) disorder, even if change never ends, because, having a definite beginning, it can never become infinitely old. Instead, it may be that disorder approaches an asymptotic maximum value of disorder, while change continues to occur. Change might become progressively less interesting, as the universe ages. Time itself may slow, but never stop entirely.
However, there is evidence that the second law of thermodynamics is not universally true when gravitational force is dominant. For example, super massive objects such as black holes are believed to drop in temperature even as they absorb energy. At large scales, gravity may be the dominant universal force and may cause the second law to be violated. Therefore, entropy may be reduced continuously by "gravitational maintenance," by episodes of universal contraction, or by some other means. The point is, we really have no idea what the ultimate fate of our universe will be. For the same reason, we cannot say the the second law requires that the universe be of finite age. Perhaps it is infinitely old.
Timeless Eternities
Another possibility is that eternity is, on net, timeless. Time runs forward in some parts in which entropy always increases, and backwards in other parts in which entropy always decreases. That is, time has opposite polarities, although in our part we can only experience one polarity. Wherever a forward-moving part of the universe contacts a backwards-moving part, time collapses to timelessness. Everything collapses to nothing. Time as well as space collapses. Black hole, anyone?
Space may be in essence that which allows time to separate into its constituent opposite polarities. "Nothing" is spread out into "something" by expansion of space. Light somehow breaks forth out of nothingness, and expands space. This is possible without violating conservation principles because positive expansion of space in which entropy can only increase is offset by negative expansion of space in which entropy can only decrease. On net, nothing is created. The light itself does not come out of nothing; light can be defined as that which expands space into its opposite polarities, and the capability of a collapsed nothingness to expand can be inherent in the state of nothingness. The expansion does not need to occur at a particular time; it can be always occurring, as an aspect of nothingness. In one part of the expanded space, time runs forward, and space is as we experience it. In another, corresponding part, time runs backwards and space is turned inside out. These corresponding parts are connected via one or more collapsed singularities of time and space. Matter condenses from light, and gravity appears in the expanded areas. Eventually, parts of the expanded space collapse under the influence of gravity caused by the coalescing of mass. Under this cosmological model, the cosmos is a timeless nothing that is balanced by opposing forces of expansion/light and gravity/mass. Time exists and flows only where space is expanded, in opposite polarities. Some Canadian physicists are now saying something similar.
Parts of the universe where time is negative may have negative polarities of space, where light condenses not into matter, but into negative matter (not to be confused with anti-matter as understood in particle physics). The negative matter exerts a sort of negative gravity. Because the negative gravity operates within a negative space, the multiplication of negatives results in the negative gravity tending to curve or collapse space, just as gravity tends to collapse space in our positive side of the cosmos. In such a cosmos, backwards time travel for living things might not be possible without the ability to translate the stuff of life between matter and negative matter while passing through a black hole. Seems pretty tricky. But purely speculative; there is no reason to believe that negative matter is favored in zones where time is negative, other than symmetry.
Even if regular matter predominates where time is negative, whether or not life can survive a backwards flow of time is an open question. All of our metabolic functions depend on processes in which entropy, on net, increases. Every known machine constructed on our side of the universe can only operate by increase of entropy. However, it's hard to rule out the possibility of constructing a machine that tolerates a decrease in universal entropy, in operation. It might even be a trivial problem. Machines and organisms operate by offsetting a local decrease in entropy with an increase in entropy external to the machine or organism, thereby satisfying the 2nd law of thermodynamics. If 2nd law ran backwards, the machine or organism could decrease entropy without having to offset with a greater external increase. What's the problem?
The greater problem in time travel may be passing through a singularity to get to the other side. It seems doubtful that information can pass through a singularity, without being destroyed. If something can exist as anything other than undifferentiated substance while passing through a singularity, we are not talking about a singularity at all. All collections of information require space to exist, and a singularity by definition is void of space. There would have to be some other way to get to the other side, if it is possible at all. Maybe information could be transmitted to the other side through something like quantum entanglement. Perhaps there is some way to access the 5th dimension and travel to the other side without passing through a singularity. Perhaps time cannot flow backwards in any space. Who knows?
Time travel by passing into a time-space of opposite polarity faces a correspondence problem. If one enters the time-space of opposite polarity at a time and place different from the point of exit, rather destructive dislocations can occur. To think about such time travel without mind-bending dislocations, it can be assumed that opposite polarities of space-time always correspond perfectly to one another, or that dislocations in time or space do not create any serious problems. If time travel is possible by entering and re-emerging from a time-space of opposite polarity, logic requires the existence of parallel universes in both polarities.
The rendering above is intended as a conceptualization of a net-timeless eternity. It is only a rendering with artifacts having nothing intended to do with the concept, unfortunately. It does illustrate opposite polarities of space connected through a singularity, but fails to show that illustrated regions of opposite polarity are separated by a higher-order dimension. Curved 4-dimensional manifolds of space-time separated by a 5th dimension and connected through a singularity are difficult to illustrate in two dimensions. Imagine it if you can.
Theology - Abrahamic
The cosmos gets a brief mention, but the story of genesis is mainly focused on the genesis of humanity, and trying to explain what the hell went wrong. We can be pretty sure our species has not been around forever, and lived in tribal hunter-gatherer societies before the development of agriculture. Genesis can be read as expressing beliefs about evolution of human society from its hunter-gatherer origins. Older specific cosmology, (creation of the cosmos) is not a major part of the story. Except in the sense that nothing material, even the sun, moon, stars, earth, is eternal. These things once did not exist, and will one day pass away. No controversy about that. So why the controversy about Genesis? Of course, the controversy is about the nature of the Creator, or the creative force. That is the point of controversy, but it cannot be resolved scientifically.