Does the Old Testament have authority for New Testament believers as scripture?
One of the most common questions that my students ask is “What’s the difference between the covenant in the Old Testament and the covenant in the New Testament?”
Often times the underlying question driving this question is related to the issue of the authority of the Old Testament for New Testament believers. They wonder, “If the Old Testament is in fact Christian Scripture, then why don’t we have to obey all of the Old Testament’s commands? This is a great question.
For starters, yes, the Old Testament is authoritative for New Testament believers. This reality is based on two simple facts. First, in 2 Timothy 3:16 it says “All scripture is inspired by God and is useful for teaching, for reproof, for correction, and for training in righteousness…” This “scripture” that Paul (the author of the 2 Timothy) is referring to is the Old Testament. At the time of Paul’s writing of this New Testament letter, there was no such thing as a New Testament. Paul must have then been referring to the Old Testament.
Second, the Old Testament was authoritative for Jesus (and the early church). As followers of Jesus, if the Old Testament had authority for him, then it does for Christians as well.
Beyond this, Jesus himself also had much to say about the perennial authority of the Old Testament as Christian Scripture (Matt. 5:17–18). Also, the New Testament writers regularly quoted the Old Testament as a basis of authority in terms of the coming of the Messiah as well as Christian ethics. In other words, the Old Testament for the New Testament writers is the controlling narrative through which they interpret life, and more specifically, Jesus and his redemptive work.
If this is the case, then what do we do with all the commands in the Old Testament? Further still, in’t there a major conflict in Old Testament and New Testament ethics? God in the Old Testament is full of wrath, but God in the New Testament is abundantly gracious! How do we reconcile these things?
Some of these questions take volumes to answer, so I want to focus on the question, how is the (mosaic) covenant in the Old Testament different than the covenant Jesus makes with believers in the New Testament?
In a phrase, the covenant that God created with the Israelites in Exodus is externaland the covenant that Jesus makes with his followers is internal.
When Jesus gave the sermon on the mount, he said things like “You’ve heard it said of those of ancient times, ‘You shall not murder…’ But I say to you that if you are angry with a brother or sister, you will be liable to judgment.” (Matt. 5:21–22)
Jesus is pointing out that even though we may not commit sinful behaviors, our attitudes and thoughts can be still be offensive to God. All outward behavior originates from within. Humanity has a behavior problem because it has a heart problem. The first covenant addressed the behavior problem. It focused on what to do and what not to do (hence the Ten Commandments). The New Testament covenant, however, addresses the internal problem.
According to the NT covenant, the Holy Spirit administers an internal transformation in that addresses not only whatpeople do, but who they are.
Jesus called the Pharisees “whitewashed tombs.” (Matt. 23:27) Jesus is saying that while they don’t violate God’s commands in their actions, on the inside they are dead and full of “all kinds of filth.”
This is the major difference between the Old and New covenants: external vs. internal.