Pharaoh said, Entreat the Lord This is the man, who, not long ago, proudly said, Who is the Lord? Who is Jehovah? He now begins to know something of Jehovah's power and justice at least, and is glad to procure Moses and Aaron to become intercessors to Jehovah for him. It appears evident from this, that Pharaoh's magicians had no power to remove the frogs which Moses had brought. So Aben Ezra observes: “He called for Moses, because he saw the magicians had only added to the plague, but could not diminish it.”
Related Commentaries of Exodus 8:8
Exodus 8:8
8 Then Pharaoh called for Moses and Aaron, and said, Intreat the LORD, that he may take away the frogs from me, and from my people; and I will let the people go, that they may do sacrifice unto the LORD.