"And the LORD said to Moses, 'I will bring one more plague on Pharaoh and on Egypt. Afterward he will let you go from here. When he lets you go, he will surely drive you out of here altogether. Speak now in the hearing of the people, and let every man ask from his neighbor and every woman from her neighbor, articles of silver and articles of gold.' And the LORD gave the people favor in the sight of the Egyptians. Moreover the man Moses was very great in the land of Egypt, in the sight of Pharaoh's servants and in the sight of the people" (Exo. 11:1-3). Everyone is on the same page, so to speak, except Pharaoh. The Egyptians are ready for the Israelites to leave and will give them many valuables to assist them. It is safe to say that the Israelites would have been free much earlier had Pharaoh not been in control. Nevertheless, God used this wicked leader to glorify His name (and He can still do such in our world today).
Then God instructed Moses to tell Pharaoh:
"About midnight I will go out into the midst of Egypt; and all the firstborn in the land of Egypt shall die, from the firstborn of Pharaoh who sits on his throne, even to the firstborn of the female servant who is behind the handmill, and all the firstborn of the animals. Then there shall be a great cry throughout all the land of Egypt, such as was not like it before, nor shall be like it again. But against none of the children of Israel shall a dog move its tongue, against man or beast, that you may know that the LORD does make a difference between the Egyptians and Israel" (11:4-7).
After this many plagues, Pharaoh knew the power of Jehovah. He was a fool if he entertained the thought that this was a bluff of some sort! God was going to deliver Israel and kill all the Egyptian firstborn. There would be no Egyptian exceptions and there would be no danger whatsoever to the Israelites! God would implement this plague personally and not by means of Moses' rod.
Then Moses declared - "And all these your servants shall come down to me and bow down to me, saying, 'Get out, and all the people who follow you!' After that I will go out" (11:8). After uttering these words, Moses, in great anger, left Pharaoh's presence. His patience was up. God knew that Pharaoh would not submit until after the death of the firstborn. Pharaoh's stubbornness resulted in God's wonders being multiplied in the land of Egypt. But soon all of Egypt would call for Israel to leave!