Exodus 5:1, 3

Afterward Moses and Aaron went to Pharaoh and said, “This is what the LORD, the God of Israel, says: ‘Let my people go, so that they may hold a festival to me in the wilderness.’ ”

Then they said, “The God of the Hebrews has met with us. Now let us take a three-day journey into the wilderness to offer sacrifices to the LORD our God, or he may strike us with plagues or with the sword.”