That river in Egypt

"My uncuffing was promised 4,000 years ago"
"..."
"Yeah I am entitled to it due to orders from the divine, recorded during the time of prophets. You cannot possibly argue with this Miss"
"...And which clay tablet says "Rennala of the 3rd millenium AD is ordered by God to gift her pet Damocles a holy unlocking of cuffs"?"
"Uhhhhh"
"Hmm?"
He knew he was got. None of the tablets he could name had that specific sentence inscribed unfortunately. He was going to have to switch strategies.