The Mosaic Law is often viewed as a burden. There are food laws, laws about uncleanness, laws about keeping Sabbaths, and a multitude of laws that many Christians of today simply don't understand. Isn't it good that the law has been fulfilled and we aren't obligated to follow this burden any more?
Yet, when Yeshua said in Matthew 5:17 that He didn't come to destroy the law or the prophets but to fulfill it, He added the following:
1.) The law would not pass away until heaven and earth passed away (Matt. 5:18).
2.) Whoever would break the least commandment or teach others to break it would be called the least in the kingdom of heaven (Matt. 5:19).
3.) Whoever would keep the least commandment or teach others to keep it would be called great in the kingdom of heaven (Matt. 5:19).
4.) Unless a person's righteousness exceeded that of the scribes and Pharisees, that person would not enter into the kingdom of heaven (Matt. 5:20).
Although Christians have traditionally believed that they are not responsible to follow the law any more, Yeshua's statements in Matthew 5 contradict that idea. Besides saying that the law would not pass away, that Christians are obligated to keep even the least commandment, and that their righteousness must be greater than that of the Pharisees, who were viewed as the most holy of people during Yeshua's time, the remainder of Matthew 5 demonstrated that Yeshua, in fact, made the law seem even more stringent. From verse 21 to verse 47 Yeshua compared the faulty understanding of the Mosaic Law to the correct understanding of God's intent of the Mosaic Law.
Matthew 5:21-22 (KJV)
Ye have heard that it was said by them of old time, Thou shalt not kill; and whosoever shall kill shall be in danger of the judgment:
But I say unto you, That whosoever is angry with his brother without a cause shall be in danger of the judgment: and whosoever shall say to his brother, Raca, shall be in danger of the council: but whosoever shall say, Thou fool, shall be in danger of hell fire.
The Jews knew that murder was forbidden by the Mosaic Law, but Yeshua included unrighteousness anger as well.
Matthew 5:27-28 (KJV)
Ye have heard that it was said by them of old time, Thou shalt not commit adultery:
But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart.
Again, adultery was a sin according to the Mosaic Law. Yeshua included lust.
Matthew 5:43-44 (KJV)
Ye have heard that it hath been said, Thou shalt love thy neighbour, and hate thine enemy.
But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you;
Here, the Mosaic Law had required that the Jews love their neighbors. They took that to mean that they did not have to love their enemies, but Yeshua included enemies and furthered the law by stating that good was to be done to them, as well as praying for them.
There are other examples about divorce, oath taking, etc. Finally Yeshua ended by saying this:
Matthew 5:48 (KJV)
Be ye therefore perfect, even as your Father which is in heaven is perfect.
Yeshua was requiring more than the following of a bunch of rules, but perfection of righteous behavior. He was helping the Jewish people of His day, and by extension, Christians, who follow Him today, understand the true requirements of the Mosaic Law. On the surface, Yeshua's laws seem to be even stiffer and more of a burden than the Mosaic Law. Consider this:
Leviticus 19:2 (KJV)
Speak unto all the congregation of the children of Israel, and say unto them, Ye shall be holy: for I the LORD your God am holy.
To be holy is to be set apart for God's service. To be holy requires perfect righteousness. God's Law, the Mosaic Law was intended to be a guideline for the people to understand how to be perfect in holiness. So,Yeshua didn't really add anything to or subtract anything from the Mosaic Law. It was already there in the Old Testament. Yeshua only clarified God's intent and gave examples to help the people understand.
So, is the law still a burden? No one is able to follow it completely. In fact, all humans are sinful. But isn't this where Yeshua's sacrificial death comes in? He paid the penalty for our sin and by our trust in His work on the cross we can be clothed with His righteousness and filled with the Holy Spirit, giving us victory over sin and the enablement to live in accord with His law, the Mosaic Law.