Morality Ch. 1: Can God’s Law Change?

God doesn’t change his mind, but he sometimes has to change his methods to achieve the same purpose. Laws that worked in the Old Testament world can have a detrimental effect today.


How can we find ethics for our world in the Bible, which was written for people living a few millennia ago? Our cultures are now so different that we can’t simply use the same rules. Even in my lifetime, many cultural practices have changed. Men used to be expected to open the door for a woman, while expecting to get a higher salary than her for the same work. It used to be wrong to attend church in casual clothing. In the language of our grandparents, it was frowned on to “make love” in public (the old term for kissing), though everyone could have a “gay old time” like the Flintstones.

The Bible itself spans hundreds of years: Abraham and David lived about two thousand and one thousand years before Christ, respectively. It spans diverse cultures, too. Ancient Palestine was divided by rival warlords fighting for religious motives, with Israel in the middle. The Roman Empire dominated the Western world by imposing an overarching legal system enforced by overwhelming military power and was ruled by occasionally unstable figureheads. Looked at this way, not so much has changed, but ethically everything has changed.

Now we have solutions for malnutrition, most illnesses, and cold weather. Communication technology means that no one needs to be lonely. Safe abortions and reliable contraception have created a new freedom in human relationships. We can bomb people without setting foot in an enemy country or starve them by economic sanctions. All these advances simply prove that when circumstances become easier, we create new forms of human suffering. We need ethics now more than ever before.

It is a mistake to look for fixed rules in the Bible, because the Bible does not have fixed rules. Should we worship on a Sabbath or Sunday? The Sabbath was part of the Ten Commandments, but that didn’t stop the early church from observing Sunday as “the Lord’s Day.” Should women cover their heads in church? Everyone agreed, from the emperor to a street cleaner, from the Jewish high priest to a drunk priest of Bacchus: all respectable women wore head coverings in public. But that changed too.

Can God change his mind? Balaam the pagan prophet said: “God is not human … that he should change his mind,” and Samuel, the first of the great Israelite prophets, agreed (Num 23:19; 1 Sam 15:29). And yet commandments, crimes, punishments, and dress codes changed through the Old Testament and into the New.

I don’t think God changes his mind. His purposes are constant and unchanging, but in order to achieve them, he has to impose different rules, provide different incentives, and encourage different behaviors whenever different circumstances occur. If we want to find ethical guidance in the Bible, we can’t fixate on the rules of one time or another. We need to discover the eternal purposes of God and consider how to achieve them.

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It’s not easy changing your mind

Changing your mind is hard, and almost impossible for some. Parents are afraid of being inconsistent, and politicians don’t like being accused of doing a U-turn. This means that even when circumstances change or when new facts emerge, they have to find a way to claim “I’ve always said that.” Religious leaders suffer in the same way – if they change their teaching, they can be charged with abandoning an ageless truth. If they honestly admit they were wrong, their following may abandon them for someone who claims to be never wrong.

The ancient world similarly regarded change as a sign of error or weakness. When Jews wanted to prove to their Roman neighbors that their religion was superior, they pointed out that the law of Moses was older than any Greek or Roman law or philosophy and that it never changes. No change is needed because God’s law is perfect and timeless. But in practice, this wasn’t true. What they never admitted was that they had changed the way the law worked, and some details in the Bible vindicate them for doing this.

The Bible contains many laws that we’d now regard as unethical. Persistent drunks should be stoned; people conquered in war should be wiped out; a poor Jew who can’t repay a debt should be enslaved; and a childless widow should marry her brother-in-law – even if he already has a wife – in order to have a son (Deut 21:20-21; 25:5; 20:10-16; Lev 25:39-40). By the time of Jesus, these laws were mostly ignored in practice. The Jews knew that some laws had changed with time – for example, the law against shopping on the Sabbath wasn’t introduced until the time of Nehemiah, at the same time that the once-a-lifetime Temple tax turned into the annual tax (Neh 10:31-32; compare Exod 30:11-16). So the law of God wasn’t changeless.

The New Testament acknowledges that the law of God changes with circumstances – for example, when the priestly family changes, the laws about who can serve in the Temple have to change (Heb 7:12). This passage argues that the priesthood reached perfection and unchangeability in Jesus, but other circumstances still change.

When we read the Bible, we are looking over the shoulders of people living a few thousand years ago, for whom it was originally written. The law of Moses was revolutionary to them because it challenged them to live different lives. It didn’t immediately transform them into a fully egalitarian society with a social-benefit system and legally protected human rights, but it did point them in that direction and pushed them as far as possible.

We can see what Israel would have been like without God’s law by examining the laws of surrounding nations at the time. For example, if a man died without a son, these laws required his widow to produce an heir by sleeping with someone from her husband’s family. This could be anyone – ranging from her husband’s grandfather to his young nephew. But the law of Moses changed this in a humane way: it restricted this law to her husband’s brother (i.e., someone roughly her age), and it gave her the choice to refuse.

U-turns within the Bible

In the Old Testament, the death penalty applied to many crimes that we now regard as merely warranting imprisonment. However, imprisonment was impossible in a community that lived in tents and later in farm shacks. Even stone walls were easy to dig through before the invention of hard-setting mortar, so there was nowhere to lock people up securely.1

Even slavery becomes more acceptable when we realize it was often short term and voluntary. In exchange for wages in advance, someone would promise to work for up to six years in return for nothing but food and accommodation. Banks didn’t exist, so this was a practical solution if your daughter needed a dowry quickly or your relatives were about to lose their farm. And Israelite slaves had more legal rights than employees in many countries today.2

Surrounding nations also had very different rules for warfare. Israel did kill or enslave people who attacked them, because letting them go merely resulted in another war a few years later, prompted by the honor-revenge culture of the time. However, surrounding nations carried out this draconian policy for all their enemies. By contrast, Israel was only allowed to kill conquered enemies who actually lived within their territory – that is, those who could sneak up for revenge during the night. When they conquered cities outside Israel, they should only kill those individuals who actually attacked them (Deut 20:10-17). Foreign leaders regarded Israel’s rules of engagement in warfare as very generous (1 Kgs 20:30).

Israelite law regarded life as precious, especially in comparison to other nations. The law of Moses punished criminal injury with “an eye for an eye” all the way up to “life for life.” However, the victim or her family could ask for financial compensation instead – and I guess that most people opted for this because it benefited them (Exod 21:23-30).3 In surrounding nations, the punishment depended on whom you had injured. Physical punishment was compulsory if you injured one of the nobility, but if you injured an ordinary person the punishment was merely a fine, while the law of Moses had the same punishment whomever you’d injured, because everyone was equally precious. And in Israel, the penalty for theft was surprisingly mild – merely return the goods or their value plus a fine. However, in the surrounding nations, a thief was executed. In other words, Israel’s law regarded all people as equal and regarded life as far more precious than things.

We can see that the law of Moses made sense back then, but is it still useful?

The value of the law today

The Old Testament law’s value today lies in its message about God’s purposes, which are eternal. Through these laws, God taught Israel that people – all people – were supremely valuable. When you harvested your field, it was compulsory to leave something for the hungry poor. If you injured anyone, you were liable to severe punishment, even if that person was a slave or an unborn baby (Exod 21:20-23).

The Jews knew that God didn’t change (Num 23:19; 1 Sam 15:29), but they also knew that the law had to change with circumstances if it was going to produce the same purposes that God intended. So when they returned from exile they felt free to change the details of the law in order to maintain those same purposes. Money and markets were much more common, and they needed to build a temple. So (as mentioned above) Nehemiah changed the once-a-lifetime Temple tax into an annual tax, and he banned markets on the Sabbath.

Increasing use of imprisonment meant that capital punishment was used much less often. By the time of Jesus, the Jews had found ways to avoid most executions; they expected God to carry out the death penalty for moral offenses by making someone die early. So when the Pharisees charged Jesus with drunkenness (using the wording of the capital offense in Deut 21:20; see also Matt 11:19), they didn’t call for the death penalty. Of course, they did want to kill him, so they had to charge him with blasphemy, which was regarded as much more serious.

Jesus and the early Christians changed the laws of Old Testament much more. Jesus ruled out polygamy, which the Old Testament allowed and even encouraged for a childless widow (Deut 25:5-6).4 Paul abrogated the law of the childless widow, saying that she could marry whomever she wanted (1 Cor 7:39).5 Paul probably wanted to sweep away other laws too, because he regarded women, slaves, and nonslaves as completely equal. But instead, he advocated voluntarily keeping the status quo for the sake of the gospel (Gal 3:28).6

God’s principles are unchangeable. He wants people to have a day of rest – Saturday or Sunday, or both; the exact rule doesn’t matter. God wants everyone to be respected, so we should follow whatever dress codes demonstrate that. The modern equivalent of women neglecting to wear head coverings might be a see-through blouse. This would be OK in a nightclub, but not in church or in other formal settings. Dress codes change, but principles don’t.

God’s laws in the Bible constantly pushed humanity forward in order to change them for the better – in the area of punishment, equality, and care of the oppressed. God’s law changed people as much as they could be changed at the time. This means that some details of God’s laws changed when society and circumstances changed. The unchangeable nature of God’s law lies in the underlying principles and purposes: the most valuable things on earth are people, not commodities. This is the unchanging ethical principle of the Bible. God supremely loves and values people, and his law teaches every generation to do the same.

But how do we know when a law can change – such as the day of the week on which we rest, or one’s dress code? And which laws are changeless – such as the law against murder or theft? How do we discern what can be changed from what is unchangeable? The next chapter finds clear guidelines.




1^ See chapter 21, “Is Gluttony a Sin?”
2^ See chapter 26, “Ending Slavery.”
3^ Financial compensation was specifically allowed for the most serious offense (v. 30), so it was assumed to apply to all others (Mekilta de Rabbi Ishmael, tractate Nezikin 8, [TinyURL.com/R-IshmaelExodus21-23]). Note that this book shortens internet links using TinyURL.com to make them easier to type into the address bar of your browser.
4^ Jesus restricts marriage to only two people (Matt 19:4; see also Gen 2:24).
5^ See chapter 11, “Jesus Outlawed Polygamy.”
6^ See chapter 14, “Wifely Submission.”



This was previously published in a similar form in Christianity magazine

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