It's more to do with the tradition that JC had to be born free from 'sin', so couldn't possibly have come from a 'soiled' womb. So his dad magically kept her 'immaculate' - free from Original Sin™ - while baking in her mum.
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'