I have a question about Exodus 4:22-23: Then say to Pharoah, ‘This is what the Lord says: Israel is my firstborn son, and I told you, “Let my son go, so he may worship me.” But you refused to let him go; so I will kill your firstborn son.’ ” This verse says that Israel was God’s firstborn son. Does this differ from the claim Jesus made in John 3:16? “For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life.” God only has one son so how could Israel be his firstborn son?
In Exodus 4:22-23 the Lord wasn’t claiming Israel as His actual son. He was using a comparison to convey Israel’s importance to Him. We would say, “He’s like a son to me.” He said since Pharaoh wouldn’t let His son go, He would kill Pharoah’s son. In this way Pharaoh would understand just how much it meant to God to have Israel freed.
It’s important to remember two things here. First, Pharaoh allowed the Egyptians to worship him as a god, and had defied the One who actually is God. It’s the highest form of blasphemy, so he brought this upon himself. Second, most people assume Pharoah’s son was a young boy. If so, he would have died in his sleep and gone directly to heaven, just like all children who die below the age of accountability. He wouldn’t have suffered at all and would have received eternal life with the Lord, something he almost certainly would not have received had he lived.