thousands of years ago
God stood before him, far enough to not intimidate (a lie. His presence was intimidating exactly as He wished. Distance made no difference to His Will), but close enough that Lucifer did not feel distanced.
That God was here boded ill in Lucifer's mind, made him worried and wary. But God did not seem angry, and that in itself made his grace traitorously happy.
But He was there for a reason.
"When I set forth the prophecies, Lucifer, I was not setting your fate, nor any others. Not truly. If I was, you all now have the choice. If I'd given you that, if I had let you choose, that was what you would have done. It was your decision to Fall, just as it was your brother's decision to be the one to Fell you."
It hurt, and Lucifer felt the inexplicable urge to deny it, to disagree, I wouldn't have. You said I would so I did, but of course his Father was right. Always.
Even if it didn't make sense to Lucifer. What did that mean? How could that be what he was going to do rather than what was predestined. Free Will does not exist.
Instead saying this, he remains silent, because he has nothing to share, nothing that God does not already know.
"The fate of the world belongs to you and your brothers now."
Lucifer said nothing, but felt, as God bade he feel, that his Father was not planning on going anywhere.
Why?
