Matthew 5:17 says, "Do not think that I have come to abolish the law or the prophets; I have come not to abolish but to fulfill" (NRSV).
What's this verse mean? My Armstrongite heritage appeals to it to argue that people should obey the Old Testament law, which includes the Sabbath, the holy days, and the food regulations. Armstrongites interpret "fulfill" to mean that Jesus added depth to the law. As the King James Version of Isaiah 42:21 states, "[H]e will magnify the law, and make it honourable." And Jesus does magnify the law in the Sermon on the Mount. He takes the Old Testament command against murder and applies it to hate, and he relates the anti-adultery commandment to lust. In the Armstrongite view, Jesus upheld the law, even as he took it to a deeper level.
Many Protestants contend, however, that Jesus "fulfilled" the law because the Torah pointed to his ministry. The author of Hebrews argues, for example, that the sacrifices of the Jewish law foreshadowed what Jesus Christ would do on the cross. And the message that Jesus' life, death, and resurrection fulfilled the law and the prophets does appear in the Gospel of Matthew. Throughout his book, Matthew says that Jesus did things to fulfill certain Scriptural prophecies. And Matthew maintains that the law also played a prophetic role in predicting Christ, for his Jesus says that "all the prophets and the law prophesied until John came" (Matthew 11:13).
For many Protestants, Jesus did not contradict or nullify the law, for his ministry has always embodied the law's very aim. Every detail of the law is a shadow of Christ. Now that Christ has come, many Protestants argue, we do not need to fulfill every literal commandment of the Torah. When the real thing is here, we no longer have to dwell in the shadows. Still, is the real thing antithetical to the shadows? No. It fulfills them.
The Armstrongites have a point when they say that Jesus wants people to do the law. After all, Jesus says a few verses later, "Therefore, whoever breaks one of the least of these commandments, and teaches others to do the same, will be called least in the kingdom of heaven; but whoever does them and teaches them will be called great in the kingdom of heaven" (Matthew 5:19, NRSV). For Armstrongites, Jesus did not abolish the law, so its commands are still binding.
But the newly evangelical Worldwide Church of God has a different understanding of Matthew 5:19. I remember reading an article in The Plain Truth that applied "these commandments" to the commands in the Sermon on the Mount, not the Torah of the Old Testament. According to this interpretation, the phrase "these commandments" relates to the commandments that follow (Jesus' commands), not those of the law and the prophets. And so, in this view, Jesus fulfilled the law and the prophets, and thus has the right to give commands of his own.
Indeed, Jesus does not always rely on the law and the prophets in his sermon. Most of the time, he does not say, "You should do such and such because the Torah says so." Rather, he appeals to himself as an authority, for the phrase "But I say unto you" occurs throughout the Sermon on the Mount.
And, yet, the commands of the law and the prophets still play some role in the Sermon, for Jesus says, ""In everything do to others as you would have them do to you; for this is the law and the prophets" (Matthew 7:12).
Some argue that Jesus supports observance of the Old Testament law, but not in a literal sense. According to this view, we do not need to observe the Sabbath or the holy days or the food laws. Rather, we fulfill the law when we follow its underlying principle: to treat others as we would like to be treated. In this interpretation, what is important is not the specific stipulations of the law, but rather its spirit, which is love.
And yet, if this is true, why did Jesus emphasize that not one jot or tittle will pass from the law until all is fulfilled (Matthew 5:18)? Jesus seems to validate the details of the law.
Speaking of Matthew 5:18, that in itself is a puzzling verse: "For truly I tell you, until heaven and earth pass away, not one letter, not one stroke of a letter, will pass from the law until all is accomplished." So the law is with us until two things happen: until the cosmos passes away, and until all is accomplished. But what if things get accomplished before heaven and earth pass away? Jesus has already fulfilled various aspects of the law, such as the sacrifices. Do we have to perform those commands literally because heaven and earth are still here?
Maybe we do some commands literally, and some spiritually. We as Christians cannot lie or murder or commit adultery on a literal level. But we don't need to offer literal animal sacrifices because Jesus is the final sacrifice.
What muddies the waters is that not everyone agrees on whether certain laws are solely spiritual or require literal observance as well. For example, do we have to observe the Sabbath in a literal sense, by resting from Friday evening to Saturday evening? Or do we fulfill the Sabbath command when we come to Christ for rest (see Matthew 11:29)?
What does God want, in terms of his law?