I found this post by Aaron Brake at Apologetics Junkie.
Excerpt:
Perhaps no area of the Old Testament is more foreign and confusing to modern-day Christians than the Mosaic Law. When reading through the Pentateuch, many believers breeze through the narrative of Genesis only to hit a roadblock when confronted with the overwhelming number of commandments, statutes, and ordinances in the last half of Exodus (not to mention the books of Leviticus, Numbers, and Deuteronomy).
Yes, this is why you have to be careful when telling people to read the Bible, because not all parts of the Bible are good for new Christians! Not only are some parts pretty difficult to read, but the new reader has no framework to interpret what they are reading! I had a non-Christian guy in my office who was starting to read the Bible and he got bogged down in the Old Testament and had no idea whether these laws applied today. It’s a major problem, which is why I recommend everybody start with John instead, then maybe Luke and Acts.
There are two ways of solving this problem that are pretty popular. One way is the covenant model and the other is the dispensation model. I think that Aaron is presenting the covenant model. In the covenant model, the Old Testament laws were part of a covenant made between God and the people of Israel.
Aaron writes:
The Law in ancient Israel served three distinct purposes: relational, instructional, and structural. The Law was given to Israel in order to form a covenant or relational agreement between Yahweh and His people… the Law functioned as a constitution which provided internal structure for the nation as a whole. It provided objective standards by which the Israelites could maintain appropriate boundaries with one another as well as neighboring nations.
Jesus formed a new covenant with a new group of people who believed in his identity as the Messiah and that his death was an atonement for sin. So only the parts of the old covenant that are explicitly carried over to the new covenant still apply to our conduct as Christians.
Aaron writes:
Therefore, the primary interpretive question readers should approach the text with is this: “What does this passage tell us about God and His holiness, about Israel and her sin, and about how Israel needed to obey in order to maintain her covenant relationship with God?” Also ask, “What specific areas of life does God expect holiness and transformation within His people?”
I recommend reading the whole post. I think this is something that should be communicated to people who are coming at the Bible from a non-Christian perspective. Maybe we should have some scholars created an optimal ordering of the books of the Bible so as not to scare people away?
Note: I haven’t really looked into this problem in detail, but the covenant model makes more sense to me.