18 Then Moses went back to his father-in-law Jethro and said to him, “Please let me return to my brothers in Egypt to see if they are still alive.” “Go in peace,” Jethro replied.
19 Now the LORD had said to Moses in Midian, “Go back to Egypt, for all the men who sought to kill you are dead.”
20 So Moses took his wife and sons, put them on a donkey, and headed back to Egypt. And he took the staff of God in his hand.
21 The LORD instructed Moses, “When you go back to Egypt, see that you perform before Pharaoh all the wonders that I have put within your power. But I will harden his heart so that he will not let the people go.
22 Then tell Pharaoh that this is what the LORD says: ‘Israel is My firstborn son,
23 and I told you to let My son go so that he may worship Me. But since you have refused to let him go, behold, I will kill your firstborn son!’”