Exodus 5:1-3

ISV(i) 1 Pharaoh Refuses to Let the People GoAfter Moses and Aaron arrived, they told Pharaoh, “This is what the LORD God of Israel says: ‘Let my people go so they may make a pilgrimage for me in the desert.’”
2 Pharaoh said, “Who is the LORD that I should listen to him and let Israel go? I don’t know about the LORD, nor will I let Israel go!”
3 Then they said, “The God of the Hebrews has met with us. Please let us go a three-day journey into the desert to offer sacrifices to the LORD our God so he does not strike us with pestilence or sword.”