Exodus 7:9

Ask thee a sign of the LORD thy God; ask it either in the depth, or in the height above. ask it...: or, make thy petition deep

Then answered the Jews and said unto him, What sign shewest thou unto us, seeing that thou doest these things?

They said therefore unto him, What sign shewest thou then, that we may see, and believe thee? what dost thou work?

And the LORD said unto him, What is that in thine hand? And he said, A rod.

And thou shalt take this rod in thine hand, wherewith thou shalt do signs.

For God is my King of old, working salvation in the midst of the earth. Thou didst divide the sea by thy strength: thou brakest the heads of the dragons in the waters. divide: Heb. break dragons: or, whales

And Moses and Aaron went in unto Pharaoh, and they did so as the LORD had commanded: and Aaron cast down his rod before Pharaoh, and before his servants, and it became a serpent. Then Pharaoh also called the wise men and the sorcerers: now the magicians of Egypt, they also did in like manner with their enchantments. For they cast down every man his rod, and they became serpents: but Aaron's rod swallowed up their rods.

Speak, and say, Thus saith the Lord GOD; Behold, I am against thee, Pharaoh king of Egypt, the great dragon that lieth in the midst of his rivers, which hath said, My river is mine own, and I have made it for myself.

But he answered and said unto them, An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it, but the sign of the prophet Jonas:

And Moses took his wife and his sons, and set them upon an ass, and he returned to the land of Egypt: and Moses took the rod of God in his hand.

And Moses stretched forth his rod over the land of Egypt, and the LORD brought an east wind upon the land all that day, and all that night; and when it was morning, the east wind brought the locusts.

But if I do, though ye believe not me, believe the works: that ye may know, and believe, that the Father is in me, and I in him.