i think that was a morman thing. (technically mormans consider themselves chrsitian)
the bible itself was written by and for dark skinned people. not necessarily black, but i dont think they had that issue in those areas. since the only white influence were invaders from the north. the ones that didnt have anything to do with the bible/torah
The original writers of the Bible were middle-eastern and to some extent Mediterannean (the cult of christianity picked up massively among the olive-skinned Romans of the Roman Empire), but would also reach people of darker skin colours who inhabited areas of northern Africa.
It wasn't made for Black people as such, but it's writers certainly were aware of dark-skinned people at the time and incorporated them into it's teachings respectively.
I don't know any cases where traditional Christianity is anti-black.
That tends to be a side-effect of white supremacy during the last 400 years, while white people have been predominantly Christian.
That's the only reason why I would imagine Christianity could be seen as anti-black, besides the individual teachings of various cults/sects.
On the argument of Air, and how it is comparable to God (Can't see it, but can feel it), the better point to make isn't the fact that you can see the air as blue in the form of the sky/atmosphere.
It's the fact that I can take a glass beaker, fill it with air, and then scientifically brown townyse the air to see what it's made of and how it reacts with other things.
You can't do that with God, which is the reason scientists don't traditionally believe in God, because he can't be empirically verified to exist.
There's no a posteriori knowledge of God.