“Yahweh said to Moses, “When you go back into Egypt, see that you do before Pharaoh all the wonders which I have put in your hand, but I will harden his heart and he will not let the people go.”
Exodus 4:21 (WEB)
Context Reading
19Yahweh said to Moses in Midian, “Go, return into Egypt; for all the men who sought your life are dead.” 20Moses took his wife and his sons, and set them on a donkey, and he returned to the land of Egypt. Moses took God’s rod in his hand. 21Yahweh said to Moses, “When you go back into Egypt, see that you do before Pharaoh all the wonders which I have put in your hand, but I will harden his heart and he will not let the people go. 22You shall tell Pharaoh, ‘Yahweh says, Israel is my son, my firstborn, 23and I have said to you, “Let my son go, that he may serve me;” and you have refused to let him go. Behold, I will kill your firstborn son.’”