As my friend and I went for a walk, we talked about our love for the Bible. She surprised me when she said, “Oh, but I don’t like the Old Testament much. All of that hard stuff and vengeance—give me Jesus!”

We might resonate with her words when we read a book like Nahum, perhaps recoiling at a statement such as, “The Lord takes vengeance and is filled with wrath” (Nahum 1:2). And yet the next verse fills us with hope: “The Lord is slow to anger but great in power” (v. 3).

When we dig more deeply into the subject of…