Within the study of New Covenant Theology there is emerging a difference of opinion over exactly what is the Law of Christ. It is the opinion of this writer that the Law of Christ is the version of God’s law that we are to obey in this New Covenant era. We are not under the Mosaic Law, which was the version of God’s law that the Israelites were under during the Old Covenant era. The summary of the law of the Old Covenant era is found in the Ten Commandments which are called the “the words of the covenant” (Exodus 34:28). In the New Covenant era we are under a new version of God’s law that is suitable for what our Father in heaven is wanting to accomplish in this era (Ephesians 2:14-18, Hebrews 7:12, 1 Corinthians 9:19-21). A summary of the law of Christ would be “love as Jesus loved” (John 13:34-35). By this we do not mean that we are to just copy what Jesus did. He was God who became man and he lived in the Old Covenant era and was obligated to obey the Mosaic law (Matthew 23:23-24). He obeyed laws that we are not obligated to obey, such as the tithe and the keeping of the Sabbath day. We do not live under the Mosaic Law (1 Corinthians 9:19-21).
We, who live in the New Covenant era, are to do what Jesus would have us to do. This means that we are to obey those laws that apply to us in this era (from Pentecost to the 2nd Coming). So, when we are describing the law of Christ we first of all mean that we are to love as Jesus loved. But having said that, we also mean that we are to live out the details of the law of Christ which are found in the teaching passages of the New Covenant era. An obvious example of the details of the law of Christ would be found in Ephesians 4:25-32 where we are given detailed instructions on how we are to care for one another. Some teachers seem to be saying that the law of Christ is the new heart of the believer. By this they mean that the motivation to live for Jesus Christ, which comes from the work of the Holy Spirit (Romans 8:5-14). It is true that all believers are God lovers, but this motivation only drives us to live for our Lord. The way we show our love for our Lord is to keep his commandments (John 14:21) and therefore obey the law of Christ.