There is a fear created in humans by their science in general and astronomy in specific that the universe and everything in it is chaotic and without meaning. That thought compels people to seek answers that reject testable science and turn to some form of hope given by generating ideas and stories that make them feel better and significant. Any good story will do, but the more distracting and absurdly otherworldly the better. Absurd because that makes it more difficult to discuss and confront in the real-world terms that are abhorred.
Because the visible aspects of physical reality are seen to be without meaning the invisible spiritual part must be where the meaning of our lives exists. What is visible obviously isn’t god or any form of good; therefore, god must exist in the invisible and thus untestable parts of reality and cannot be understood by physical means. Because spiritual reality is scientifically untestable it is then postulated and believed by many that that is where the meaning of our lives must lie. It must be there or our lives are totally and ultimately meaningless, and that is impossible to accept because if it were true we would all die of despair.
We live and all nature lives too, and we haven’t died of despair and therefore god exists and all of our lives are meaningful.