The Cosmological argument generally goes something like this, whatever begins to exist has a cause, the universe began to exist, therefore the universe has a cause. This post is not about the weaknesses in that argument. What I want to do instead, is address the weakness in this approach to apologetics. It has long been the case, at least since the Enlightenment, if not long before that), that Christians have thought they can prove the Bible, and consequently, Christianity, if only they can prove that the universe has a creator. Many apologists make the argument as if they have proven Christianity true by making such an argument. There are other arguments that are often used, especially by trying to argue using specific features of the cosmos like, design, etc. However, they couldn’t be more mistaken. Instead, you end up arguing for a generic god. I have tried many times on my own to connect these arguments together, and have never been able to make the connection logically. At best, you have a general theistic god, at worse, a deistic god, it could be the God that Christians worship, but not necessarily. This is not to say there is no good that can come from natural theology. Natural theology is an excellent project, especially by scientists who are also theologians, such as John Polkinhorne. A doctrine of creation is important too, within a Christian context once we already understand Jesus and the implications for the world and the cosmos.
Christian apologetics has to start with Jesus, who is the center of our faith. To get into a debate based on creation is to miss the central point. If all you wish to do is establish that there is a god, then debate away, but, logically, you will then not be able to make the connection to Christianity.