Exodus 7:10 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. 11 Then Pharaoh also called the wise men and the sorcerers: now the magicians of Egypt, they also did in like manner with their enchantments. 12 For they cast down every man his rod, and they became serpents: but Aaron's rod swallowed up their rods.
[Patriarchs & Prophets pp 263] Every punishment rejected would be followed by one more severe, until his proud heart would be humbled, and he would acknowledge the Maker of heaven and earth as the true and living God. The Lord would give the Egyptians an opportunity to see how vain was the wisdom of their mighty men, how feeble the power of their gods, when opposed to the commands of Jehovah. He would punish the people of Egypt for their idolatry and silence their boasting of the blessings received from their senseless deities. God would glorify His own name, that other nations might hear of His power and tremble at His mighty acts, and that His people might be led to turn from their idolatry and render Him pure worship.
Again Moses and Aaron entered the lordly halls of the king of Egypt. There, surrounded by lofty columns and glittering adornments, by the rich paintings and sculptured images of heathen gods, before the monarch of the most powerful kingdom then in existence, stood the two representatives of the enslaved race, to repeat the command from God for Israel's release. The king demanded a miracle, in evidence of their divine commission. Moses and Aaron had been directed how to act in case such a demand should be made, and Aaron now took the rod and cast it down before Pharaoh. It became a serpent.
The monarch sent for his “wise men and the sorcerers,” who “cast down every man his rod and they became serpents: but Aaron's rod swallowed up their rods.” Then the king, more determined than before, declared his magicians equal in power with Moses and Aaron; he denounced the servants of the Lord as impostors, and felt himself secure in resisting their demands. Yet while he despised their message, he was restrained by divine power from doing them harm.
Exodus 7:13 And he hardened Pharaoh's heart, that he hearkened not unto them; as the Lord had said. 14 And the Lord said unto Moses, Pharaoh's heart is hardened, he refuseth to let the people go.
May The Lord add His blessing to the study of His word. God bless!