User blog comment:Woest/Celestial Spirit King and Zeref/@comment-7418318-20131215093102

It was never said that the entire Eclipse Gate came from the book of Zeref, only that it used information from it. So it's possible that the entire part about Celestial Spirits came from the Royal Family thus there is no actual proof that Zeref knows about Celestial Spirit Magic.

I'm not saying that it's impossible for Zeref to know - actually with his long livespan he's even very likely to know - I just object to the word "proof" here. Maybe switch it to "indicate" or "hint"?

Regardin the theory itself: If Zeref really knew everything about the Eclipse Gate he would surely have noticed it's constuction. Thus wouldn't he either have tried to help them with their plan to kill him in the past or tried to stop them, rather than just standing at the sidelines and sending in a spy?