Somewhere along the line, it seems to me, there has been an assumption that all the stories in the Bible have to be something for children. If some account is disturbing, then there is a problem with the Bible — as if the Bible was written just for the sake of kids.
Some people object to the Bible on these grounds, even making fun of it. After all, we read about adultery, murder, incest, rape, children sacrificed to idols, and other horrific situations. We read of concubines getting hacked to pieces, kings brutally assassinated, and some of the "heroes" committing terrible sins. This is not really the stuff we want to tell our children about. Therefore, some conclude, the Bible is not a good book.
Those who think this way are very much missing the point of the Bible. The Bible was never meant to be a child's storybook. It's not about just trying to engender nice platitudes and have entertaining classes. Don't misunderstand. We need to be teaching our children the Bible, but there is a reason there are different levels of learning and teaching. Children may not be ready for some of what we read in the Bible, but there is always plenty there to talk about with them. As they grow, they will get to know the Bible more fully, and, if taught well, will understand why the ugliness is there.
What this shows us is that the Bible is a book of reality. The writers do not sugar coat. They don't gloss over the faults and sins of the main characters. They don't hide the plots that make normally good men look bad. The Bible reflects what really happens. It teaches us head-on about the loathsome nature of sin. Eventually, all people need to know about this and understand the Bible's purposes.
In other words, the Bible shows us exactly why we need the grace of God. All of the ugliness of the sins and evils we read about are finally wrapped up in the suffering Servant as He hangs on the cross. Therein we find the full force of sinful disgust being conquered by the abundant love and grace of God. If we don't see the problem first, we'll never understand the need for, and depth of, God's response.