Exodus 8:24-27

24And Jehovah did so; and there came dog-flies in a multitude into the house of Pharaoh, and [into] the houses of his bondmen; and throughout the land of Egypt, the land was corrupted by the dog-flies.

25And Pharaoh called Moses and Aaron, and said, Go, sacrifice to your 1God in the land.

26And Moses said, It is not proper to do so; for we should sacrifice the abomination of the Egyptians to Jehovah our 2God: lo, if we sacrificed the abomination of the Egyptians before their eyes, would they not stone us?

27We will go three days' journey into the wilderness, and sacrifice to Jehovah our 3God, as he shall command us.