Exodus 5:2-3

But Pharaoh said, “Who is the LORD that I should obey His voice to let Israel go? I do not know the LORD, and besides, I will not let Israel go.” Then they said, “The God of the Hebrews has met with us. Please, let us go a three days’ journey into the wilderness that we may sacrifice to the LORD our God, otherwise He will fall upon us with pestilence or with the sword.”