Prologue (Not a prologue: That would be a chapter in itself: This is more of a epigraph)
Equally, as it appears to be a fable, dress it up as such. Read the Bible and try and get that same sense of foretelling it uses.
...and it was foretold that in the age of steel, on a night were the Earth itself weeps, a man that will shape the future of the world will be born, but in order to bring salvation, he must sacrifice the one closest to him, the one and only person he will ever truly love. He will do this, but he shall be doomed to a life of solitude and loneliness, as is the path of the Great One.
Have to say it, cliche. Although in a fable that might work. With your main story though, try to steer it away from this route.
This is the destiny of the Great One, and it is the only road he shall travel.
Should it be better with "the only true road he can travel"? As that stops it being linear
Chapter 1
The storm was raging long and hard,Dark and stormy night? AVOID! the thunder shook the very Earth, making it seem as if(Weak. And who's describing this?) Hell itself were trying to surface. Lightning struck the land, scarring it with fires that would burn for days. Villages were flooded, water ran down from the mountaintops, making it seem that even the Earth itself were in great pain.(Weak use of the storm. If you're going for a dramatic opening, specify certain problems and ramp it up to 11. Especially if you're going Biblical.)
On this, the most chaotic of nights(Repetition), a child would be born.(Most nights) A child destined for great events, a child who would determine the future of all creation.(Sorry...yawn set in. This whole first paragraph seems as if it would be better in the fable part of the prologue. Then you can make it as unreal as possible, before starting with the aftermath in Chapter 1)
In a dark cathedral, high upon a hilltop, a woman's cries were lost in the torrent of rain and thunder. (Now THERE's your first line for Chapter 1...put that in there at the start and you'll hook your audience)
The midwives and the doctors did all they could to help, but the woman knew her time was coming. With a final push she delivered the child into the world, and with her dying breath whispered "Go forth, my son, Gariah..."(Too fast. Really too fast. This is a great dramatic moment and it deserves to be milked for all it's worth)
And with a final flash of lightning, the woman was no more.(Don't link the two events so closely, because it sounds like the lightning struck her. The last three lines could easily form your first chapter of 6 pages)