Evangelicals have recently rediscovered the law of Christ (1 Cor 9:21; Gal 6:2). This rediscovery of Christ’s law arose out of concern over how to live out the Old Testament law. Christians don’t really sacrifice animals today or keep the Sabbath holy (which is Saturday). In fact, evangelicals worship on the first day of the week to celebrate the Lord’s resurrection (Sunday). Although Reformed folk have held to a threefold division of the law (civil, ceremonial, and moral) and argue that Christians should only follow the moral elements of the Old Testament law, this theory is fairly artificial. So what is moral? Why don’t Christians need to keep the Sabbath today? Is that any less moral than taking the Lord’s name in vain?
The ancient church skipped this argument, and followed the law of Christ. For example, Ignatius writes to the Romans in around 100 AD complimenting the Romans on “observing the Law of Christ.” It was natural for Ignatius to use the Apostle Paul’s description of the teachings of the Messiah, the law of Christ (Gal 6:2; 9:21).
With Paul and Ignatius, I suggest Christians start here when considering how to live the Christian life. Yes, many many many specific questions still need answering. Still, having the right foundation for Christian ethics will help believers to answer the more practical questions that arise throughout the course of life.