I think the worst part of the Kalam Cosmological Argument is the presumptive nature of the whole thing. While the Bible answers the question of cosmology with "God did it", the cosmology in the Bible that "God did" isn't starting the inflationary expansion of the universe or causing the big bang. But rather painstakingly and skillfully (Psalms 19:1 The heavens declare the glory of God; and the firmament sheweth his handywork.) created a large metal-like dome held up by strong pillars to keep the cosmic ocean divided and the waters above the heavens and below the Earth apart.
In the Bible, we live under a large metal like dome of heaven, with little twinkly lights stuck into it and above the heavens there's the waters and below the earth the other waters which God so helpfully divided up in Genesis. The Bible's answer to this is "God did it".
-- That's fine, but you don't get to copypasta that answer onto a modern cosmological framework and suppose that the authors of the Bible had any freaking clue what the universe was like. "God did it" is the answer the Bible gives to the metal-like dome protecting us from the cosmic ocean, you don't get just re-appropriate that answer to new cosmologies that are less horribly wrong. It's like saying Jesus cured diseases. No, he shooed out demons that caused diseases. You don't get to use the modern understanding and the answer "God did it", because the "God did it" was to answer in the context of the primitive understanding. The Bible says God is the reason the sun revolves around the Earth, sorry Bitches, no backsies!