If God is unchanging, then what God ordains can’t be changed.
So if we argue that slavery is ordained by God, then it’s blasphemous to abolish it. If we argue that God ordained that women be stay at home mothers, then it’s blasphemous for them to have a career. If God ordained marriage between a man and woman only, then it’s blasphemous for anyone else to marry.
By couching Christian positions as God’s will, churches perpetuate inequality as divine. It allows them to overlook oppression by saying, “Oh, I don’t understand why God made it that way. I just trust he did it for the right reason. We will know in the end.” It absolves them of complicity. It makes them feel as if they’re being objective and balanced, as if they aren’t actually homophobic, racist, or sexist.
They fault God for their bigotry. And they don’t change.