Exodus 8:24-26

King James Version

²⁴ And the Lord did so; and there came a grievous swarm of flies into the house of Pharaoh, and into his servants' houses, and into all the land of Egypt: the land was corrupted by reason of the swarm of flies.

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

²⁶ And Moses said, It is not meet so to do; for we shall sacrifice the abomination of the Egyptians to the Lord our God: lo, shall we sacrifice the abomination of the Egyptians before their eyes, and will they not stone us?