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. 2 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.” 3 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.
4 Then Moses said, “Thus says the Lord: ‘About midnight I will go out into the midst of Egypt; 5 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. 6 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. 7 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.’ 8 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.” Then he went out from Pharaoh in great anger.
9 But the Lord said to Moses, “Pharaoh will not heed you, so that My wonders may be multiplied in the land of Egypt.” 10 So Moses and Aaron did all these wonders before Pharaoh; and the Lord hardened Pharaoh’s heart, and he did not let the children of Israel go out of his land. Exodus 11:1-10 NKJV
This is the promise that was made from the start, before any of the other signs or plagues.
Exodus 4:22-24 "Then you shall say to Pharaoh, 'Thus says the LORD, "Israel is My son, My firstborn. 23"So I said to you, 'Let My son go that he may serve Me'; but you have refused to let him go. Behold, I will kill your son, your firstborn."'" 24Now it came about at the lodging place on the way that the LORD met him and sought to put him to death.…
How dare he! Who is God to take the son of the great and mighty Pharaoh? Are these not Pharaoh's slaves, so why should he relinquish ownership to the One that refers to them as His firstborn? This was the warning from the beginning, and it was for a time avoidable. The promise, oddly enough, reflects the refusal of the life of God's own Son. From the fall He promised a seed that would conquer sin and death. It is the same warning, all have sinned and fall short of the glory of God. God hates sin, and though He provides the way out, we would refuse, unless there is a change of heart. Pharaoh's heart remains hardened. He still believes that he owns this world, his life and the lives of those he would use. God created life, he created free will, but in the fall from glory the will of man has become slave to his lust and arrogance. The name upon Israel as firstborn, is by the willful mercy of the Lord. They were all dead in their trespasses too, just like the Egyptians, but when all who are born into sin die in their sin, is that not justice? For the wages of sin is death, but the gift of God is eternal life. When we receive Jesus as Savior, it is not what we deserved, but rather an extraordinary gift from a God who hates sin, yet chooses to show mercy.
Do not think that I came to abolish the Law or the Prophets; I did not come to abolish but to fulfill. 18"For truly I say to you, until heaven and earth pass away, not the smallest letter or stroke shall pass from the Law until all is accomplished.…Matthew 5:17&18
