In modern days, we spend lots and lots of energy on the Ten Commandments. I think this is good energy, as those ten summarize well the covenant between God and Israel at Sinai and well summarize the principles that apply through this day. No amount of "we live under grace in this time" will convince me that stealing, murder, or adultery are now acceptable. This means even you, Congress and the White House. Even for you.
One can take the principles of the Ten Commandments and then spend quite a bit of energy debating how those flesh out in real life. For example, certainly I should not go forth and murder someone, but what happens if my cattle get loose and kill someone? Does that make me a murderer? What about assaults? How do I know what "honoring my mother and father" means?
With questions like this, we come into Exodus 21 (link). It is easy to get bogged down into these laws, and they constitute much of the remainder of Exodus and Leviticus. Here is the main thing that we should take from these laws:
There are implications in day-to-day life if you are going to live in covenant with God.
Those implications range from the biggest of issues to the smallest; from willful murder to negligent injury. It takes time to grind through how all of it would apply: compare how, in 200 years, the United States still cannot fully settle on the implications of the Constitution of the United States of America. Even the settled aspects, like judicial review as stated in Marbury v. Madison, are questioned by both political parties when convenient.
The people of Israel, though, do not have time to have their judges haggle out what constitutes "keeping the Sabbath." That's actually one of the issues we see coming forward to the New Testament era: over time that commandment became the basis for a substantial body of expectations and requirements. Instead, as we come through this passage and into the others, we see God give them directly the case law from which to settle those disputes.
We see that ethics and daily life can and should be informed and driven by God's commands and see how those come forward. Now, I am not going to subject you, dear blog readers, to a full-length exposition on the applicability of the whole Old Testament Law on the New Testament believer, but it is important to consider two things: 1) God does not change; 2) Culture and society do change.
Throughout the Law, what we see is the God-given direction for how an agrarian society lives in light of the covenant. Everyone at the time of the Law farmed, so giving and taxation are expressed in terms of produce and agricultural products. (Really, everyone did—the closest to a non-farmer was a Levite, supported by the giving and taxation.) There were no major government structures, there were no big highways to maintain, so the Law looks different than it would today.
An additional aspect of this issue comes from the situation of the time: the Israelites have lived under Egyptian law and are going to be influenced by other laws in the region. They have to find from their location what God truly wants. The Babylonians may have a good idea, but is it godly? That is part of the question at hand.
That's important: we have to extract the eternal principles as reflected in the more specific wording present. Here's an example:
Take a look at Exodus 21:28-29. Oxen goring people to death is not a major issue in modern America, but personal responsibility is. Here is the principle: an animal may do unpredictable things, and no person should be considered responsible for those things. Unless they knew it would happen. In the same way, there are unpredictable issues in life today—and it is reckless to hold someone responsible for those. However, if it is painfully obvious that those issues were predictable then the responsible party is just that: responsible.
Further, one should look at Exodus 21:24. This verse is often maligned today, most notably by those who quote Gandhi that "An eye for an eye just makes the whole world blind." The world situation then, though, was different. Look back at Genesis 4:23-24. Lamech voices the world's perspective: I don't get even, I go one up.
This is prohibited by God's law. Justice is about bringing equity for harm, not about vengeance beyond that equity.
Today's Nerd Note: Much ado is made of the laws regarding slavery. The presence of these laws have wrongly been cause for the perpetuation of slavery and for the dismissal of all of the Bible. The situation at the time was a world full of slavery. In a non-monetary society, slavery is practically unavoidable. Eventually, someone will have nothing to offer for trade besides their own labor for a time. Anyone in that situation becomes a slave—even if just for a season. The other source of slaves was conquest in battle. Given the choice between slavery and extermination, some chose slavery and others chose death.
As such, the Law provided much regarding the treatment of slaves. It was a reality of the times. It was unpleasant then, but we ought not take the presence of legal rules as absolute permission for the behavior now. Likewise, we no longer expect to see brothers marry widows or any other form of polygamy.