Arguments over the existence of God would be an entertaining waste of time, for proponents of either side, except that some people take it so seriously that it affects their attitude about the governance of society.
It is the case that a significant number of people who believe in the existence of God see science, and even rationality, as something foreign to a belief in God. Therefore for society to promote science is to be ‘anti-God’ — and not merely to be refusing to accept God, but to be attacking a belief in God.
From there, it is not far to go to conclude that ‘secular humanism’, in particular any secular approach to just governance, is also anti-God.
The inevitable next step is to require ‘God-based’ governance.
Yet, if God created us, he created us with a rational capacity that we can use to try to understand the material existence we experience. We can even use our rational capacity to explain to ourselves what just governance must be.
“Real justice” is a strictly rational approach to just governance that does not even involve so much as one secular belief — so there is no privileging of secular beliefs over religious beliefs. Real justice boils down to a handful of absolute prohibitions (so, no ‘moral relativism’ here): no killing, harming, coercing, lying, cheating, or stealing to get what you want. There is nothing anyone who believes in God could disdain in that.
The ethic of real justice (i.e., mutual respect in effecting choices) can also be applied to the structure and functioning of the political process (reinforcing democracy) and the economy — grafting a “democratically distributed income” onto the existing economy, making it self-regulating while eliminating unemployment (at no cost to anyone), poverty (without having to redistribute anything), taxes (of every kind), and public debt (at every level of government), with more sustainability (even without additional regulations or any changes in behavior). Liberty would be maximized as an outcome.
A brief (“5 min read”) summary of that approach to justice is here in Medium.