It's this relationship that is the Grail and if the sight of the Grail is extinguished on earth, then mankind is doomed but then so is Satan and that's why Satan hasn't destroyed mankind. His purpose is to win the grail for himself with all these mystery religions as one of his tools. But his battle to win the grail has already been lost in the higher planes because Satan was thrown out of heaven. The result of this is the increasing turmoil on earth, as mankind tries desperately to cling on to the ego, which should only have been a vessel for the spirit and a gateway back to the divine.
This is why Jesus is returning yet again because the world is at another such crisis point. This time, though, his appearance is not physical but spiritual and by us adopting his consciousness and still retaining our own individuality, our physical bodies can be transcended.
Again these are my personal thoughts!