When teaching the Exodus story, a question like this typically arises:

How could God bring such plagues on Egypt? Pharaoh was the one who was doing the bad things. Aren’t the plagues an example of God indiscriminately wiping people out with judgment?

The Torah anticipates this objection, and Genesis 18:22–33 speaks directly to it. Listen to what Abraham says to God when he finds out that God is about to destroy Sodom:

There’s no way you can do something like this, killing the righteous with the wicked so that the righteous are treated just like the wicked! Not for you, the judge of the whole earth! Will he not do what is just?! (Genesis 18:25)

The Point

This episode in the life of Abraham prepares the reader for the Exodus and Joshua. It’s similar to the function of Matthew 5:17, where just before teaching the six so-called “antitheses,” Jesus says, “I know you are likely to misunderstand what I’m about to say so let me be clear: I did not come to do away with the Law and the Prophets. Don’t hear me that way. I’m not contradicting them; I’m fulfilling them.” Similarly, Genesis 18 says, “You are about to read multiple major stories about God bringing judgment and destruction on people. Don’t misread these stories and think that Yahweh is indiscriminately destroying the righteous with the wicked. That’s not who he is.”

Explicit Exodus

There’s good reasons in the text around Genesis 18 to think that the author intended the passage quoted above to serve as interpretive guide rails for upcoming passages of judgment, beyond the story of Sodom. The Exodus story haunts this section of Genesis. It’s present both explicitly and implicitly. For example, the Exodus story is explicitly mentioned in Genesis 15:12–16. Yahweh tells Abram that his offspring will be slaves in a land that isn’t theirs (Egypt) for four hundred, and they will come out of that land with great possessions.

Implicit Exodus

The Exodus story is implicit in the story of Abram and Sarai’s trip to Egypt in 12:10–20:

• Abram and Sarai go down to Egypt because of a famine, just like Jacob’s family does leading up to the Exodus.
• Pharaoh takes possession of Sarai like the later Pharaoh of the Exodus takes possession of Israel.
• In Abram and Sarai’s story, Yahweh brings great plagues on Pharaoh just like he will later do in the Exodus story.
• Abram and Sarai leave with great possessions, like Israel will in the Exodus.
  

Abram and Sarai’s story is told on analogy to the Exodus. In Genesis, major patterns of Israel’s story play out in the life of Abraham.

Now, back to the context of Genesis 18:25. In the next scene (Gen 19:1–3), the messengers of Yahweh come to Lot in Sodom, and they all eat a feast of unleavened bread. They eat unleavened bread just before God brings judgment on Sodom and makes a way out for Lot. In essence, Genesis 19:1–3 makes clear that the judgment of Sodom and Gomorrah is supposed to be understood on analogy to the Exodus, too. Lot eats a “Passover meal” of unleavened bread just before the LORD makes an Exodus way for him, delivering him from the “plagues” poured out on Sodom.

Conclusion

If you see the way the Exodus story is explicitly and implicitly present in and around the context of Genesis 18, it makes sense to read the Exodus story and the story of Sodom’s judgment on analogy. If you set these stories side-by-side and you recognize that the author of the Torah wants you to read this way, Abraham’s prayer in Genesis 18:25 speaks volumes about how you are supposed to understand the Exodus plagues. Yahweh is not a god who does injustice. He does not destroy the righteous with the wicked. He didn’t do that in the Sodom story, and he will not do that in Exodus or Deuteronomy or the book of Joshua.