Answer
In the Bible, the Lord is referred to as Father, and we have to understand what that means wherever it appears. The Bible assumes that we will understand he's a good Father. The writers of Scripture were well aware of evil fathers, bad fathers, fathers who didn't do what they were supposed to do, and the assumption is, the demonstration is, that the Lord is a father who does do what a good father does. In fact, any good thing that a human father does, he does because the Lord is the ultimate good Father who has created us and given us the ability to do good things. Well, in the book of Exodus, the Lord says, "Israel is my son." When he said that, everyone who would read that statement or hear that statement would understand that there's a relationship between the Lord and Israel that has basically international diplomacy meaning. When the great kings of the ancient Near East wrote to each other, they would refer to one another as brothers. When they wrote to their inferiors or talked about their inferiors, they might talk about them as son, and meanwhile the lesser king or ruler official might speak of the king he's responsible to as father. And this was a way of helping one another understand the nature of the relationships that they had with each other. The assumption was if a king said that someone was his son, whether he was a biological son or his deputy king, anyone who heard that statement would need to understand, "Well, you need to respect this son of mine, because all of my authority resides in him." Meanwhile, the son would understand the nature of his responsibilities to the greater king, the king to whom he was responsible. So, sonship, fatherhood were metaphors for helping people understand the nature of God's relationship to the nations, to the nation of Israel per se, and to Pharaoh this would have been, a great way to understand that he needed to do what the Lord said. When God called Israel his son, he was explaining to everyone who heard this that they have a permanent relationship; just as a father and son who are biologically related have a permanent relationship, so Israel and the Lord would have a permanent relationship that would be ultimately conveyed by a covenant. So this is part of covenant language to call Israel a son.
When the Lord calls Israel his son in the book of Exodus, he's using language of diplomacy in the ancient Near East. That language would clue everyone in to the fact that they would have ultimately a covenant relationship, a relationship that the Lord intended to be permanent just as a father and son are permanently related biologically or as a result of adoption. So, the Lord says Israel is my son. Pharaoh should know from that that he is responsible to treat Israel with respect, the respect due to Israel's father, so to speak. Pharaoh wants no part of that. When the Lord talks to Pharaoh about bringing Israel out of Egypt, the issue is not strictly whether the Israelites would have an opportunity to take a three-day trip to the wilderness, and everyone knew that. Everyone knew that the real issue was whether Pharaoh would recognize the Lord's superior authority.
Answer by Dr. Dorian Coover-Cox
Dr. Dorian Coover-Cox is associate Professor of Old Testament Studies at Dallas Theological Seminary.