Exodus 8:27

25Pharaoh called for Moses and for Aaron, and said, “Go, sacrifice to your God in the land!”

26Moses said, “It isn’t appropriate to do so; for we shall sacrifice the abomination of the Egyptians to the LORD our God. Behold, if we sacrifice the abomination of the Egyptians before their eyes, won’t they stone us?

27We will go three days’ journey into the wilderness, and sacrifice to the LORD our God, as he shall command us.”

28Pharaoh said, “I will let you go, that you may sacrifice to the LORD your God in the wilderness, only you shall not go very far away. Pray for me.”

29Moses said, “Behold, I am going out from you. I will pray to the LORD that the swarms of flies may depart from Pharaoh, from his servants, and from his people, tomorrow; only don’t let Pharaoh deal deceitfully any more in not letting the people go to sacrifice to the LORD.”