Exodus 8:25-26
8:25 Then Pharaoh summoned Moses and Aaron and said, “Go, sacrifice to your God within the land.”
8:26 But Moses said, “That would not be the right thing to do, for the sacrifices we make to the Lord our God would be an abomination to the Egyptians. If we make sacrifices that are an abomination to the Egyptians right before their eyes, will they not stone us?