The time to pray is over ...


Then the Lord said to Moses, "Why are you crying out to me?" Tell the children of Israel to march.
Exodus 14:15

Jehovah said to my Lord:
Sit at my right hand,
Until I make your enemies your footstool. Samos 110: 1

God sent 10 plagues on Pharaoh until he bowed his knees and set his people free to worship.
That is what happens with a Pharaoh who does not want to obey God.