Darksied is based on the Christian version of the Devil and is also a representation of the worst of Christianity. The Anti Life equation is what people across generations have sought after: proof of their god to justify their harmful actions.

The New vs Old gods have a bunch of mythological undertones with "good" ones being based on older mythologies and reinventing them, while Apokolips represents a rejection and utter destruction of all other ideas, like Christianity after Jesus.

In modern comics, like Preacher, he's compared directly to Jesus.