Do Christians have to follow everything in the Old Testament?

[Note- I know it’s long, there is a summary at the end!]

People often ask questions along the lines of, “The Bible commands people to do x/y/z. How can you believe that?” While the Bible has many beautiful parts, it is true that there are some that are challenging. Questions about these may come from Christians trying to better understand their faith, or come as challenges from non-Christians. I’ve seen billboards sponsored by anti-religious groups that put these passages on display as a way to discourage faith. However, I do think there are good answers to these questions, and already have written a little about this here.

Today I want to look at another part of the answer – the difference between the Old and the New Testaments in the Bible. Sometimes it seems that the person asking the question doesn’t have a sense of the difference in how we approach these two sections of the Bible. The “Old Testament” refers to all of the inspired books written before the time of Christ, and corresponds to the books revered by the Jewish faith. The “New Testament” refers to the writings inspired after the time of Christ written by the apostles and other disciples.

The reason that this is relevant is that most of the challenges I see based on difficult passages tend to come from the Old Testament, while the Christian scriptures would be more identified with the New Testament. Thus, it seems like an easy answer would be to say that any text quoted from the Old Testament is now invalid for Christians – like a lawyer trying to appeal to an outdated version of the law (the early writer Marcion actually tried an approach somewhat like this). This response, though, does not really fully respect the teaching of Christ. He reaffirmed some portions of the Old Testament, while not binding us to follow everything it contains. Here are a few key points about how Jesus spoke of the Old Testament.

1. Jesus affirmed that He was not abolishing everything in the Old Testament: “Do not think that I have come to abolish the law or the prophets. I have come not to abolish but to fulfill” (Matthew 5:17). In other places He teaches the continued validity of some of the commandments of the Old Testament (eg, Luke 18:20). The important word here is that He came to “fulfill.” This is different from simply repeating old laws, and different from simply creating completely new ones. It is about bringing the commandments to the purpose they had from the beginning.

2. Jesus showed that some teachings in the Old Testament needed to be understood in a deeper light. This is most clear in His “Sermon on the Mount” in chapters 5-7 of Matthew. He repeats a similar formula to this one: “You have heard that it was said, ‘You shall love your neighbor and hate your enemy.’ But I say to you, love your enemies, and pray for those who persecute you…” (Matthew 5:43-44). The Ten Commandments given to Moses taught basic truths, but that did not mean that was the limit to what God desired for our behavior. There is much more to the love of God and neighbor than simply avoiding murder!

3. Jesus showed that there were commandments in the Old Testament that flowed in part from hardness of heart. For example, when asked about divorce Jesus said, “Because of the hardness of your hearts Moses allowed you to divorce your wives, but from the beginning it was not so” (Matthew 19:8). In other words, we should recognize that the Old Testament teachings were steps along the way to perfection, not the final reality. I also think it is very important to realize that this sort of correction is already included in the Old Testament itself. For example, God says to the prophet Ezekiel, “Do I find pleasure in the death of the wicked? … Do I not rejoice when they turn from their evil way and live?” (Ez 18:23). Or, in Isaiah: “‘What do I care for the multitude of your sacrifices?’ says the LORD. ‘I have had enough of whole-burnt rams and fat of fatlings; in the blood of calves, lambs, and goats I find no pleasure.’” (Is 1:11). So, even in the Old Testament itself we see evidence that God is preparing for a fulfillment of the Old Testament commands to coincide with their true purpose.

4. In addition to these forms of elevating/restoring given commandments, Jesus teaches that some parts of the Old Testament will be replaced. In regards to worship, He tells the woman at the well, “Believe me, woman, the hour is coming when you will worship the Father neither on this mountain nor in Jerusalem… true worshipers will worship the Father in Spirit and truth” (John 4: 21, 23). As The Letter to the Hebrews also shows the way that Christ’s offering on the Cross fulfills (and hence replaces) the offerings of animals in the Old Testament. As Catholics we believe that this new worship is connected to Jesus’ command to continue what He did at the Last Supper (“Do this in memory of me,” Luke 22:19), which is what we do at Mass.

5. Finally, I want to end by saying that Jesus ultimately entrusts the Apostles with the responsibility of discerning what is still required. We see this in the Acts of the Apostles as they address the dietary restrictions and the question of circumcision (Acts 11 and Acts 15, respectively). While I only referenced a small number of the teachings Jesus gives on the matter, even the full list would not address every part of the Old Testament! Here we see one of the reasons why Catholics believe in a continued teaching authority that exists in the Church.

Summary: This is one of the longest posts I have written, even though it barely scratches the surface! Therefore, I thought I’d end with a tl;dr type response from the great Thomas Aquinas (Summa Theologiae I-II, q. 100-105). The Church has basically concluded that commandments in the Old Testament can be broken down into three categories: moral, ceremonial, and judicial. Moral commands came from the demands of doing good and avoiding evil, and still bind – often with a deeper explanation given by Jesus. Ceremonial commands had to do with the worship of God, and are fulfilled in the worship of the New Testament centered on the offering of Christ on the Cross, replacing the old practices. Judicial commands covered other aspects of life among the Israelites concerning community order, and weren’t about enduring questions of good/evil. These were only intended to remain for a time, and were annulled by the coming of Christ.

I hope this helps in some way to clarify how we understand the Old Testament as Catholics. When someone questions a particular passage, it’s essential to take the time to understand how it fits into this larger picture. God bless!