These two verses are sometimes used to prove that everything in the Old Testament (the Law and the Prophets) is as binding on Christians as it was binding on the Jews in the Old Covenant. From the Sabbath law written on the tablets of stone, to the “storehouse tithing” laws, to the discipline and punishment of rebellious children, to the dietary and civil laws in Leviticus--some say all of these biblical laws of the Old Covenant are as binding upon Christians as they were the Jews. Jesus, however, is clearly teaching just the opposite. Jesus reveals to His disciples how He came to fulfill (plerosai) the Old Testament (the Law and the Prophets). He then proceeds to boldly declare that "the Law" will pass away when "heaven and earth" pass away because the Law will have been completely fulfilled ("accomplished" NAS).
Western Christians think of "heaven and earth" as the sky and the terrestial ball we call earth. But when Jews would refer to the establishment and/or fall of governments or covenants, their prophets would employ the language of creation and/or destruction of "heaven and earth." For example, God describes His agreement with the Jews in the Old Covenant in this manner: "I have put my word in your mouth and have covered you with the shadow of my hand, to establish the heavens, to found the earth, and to say to Zion, 'You are my people'" (Isaiah 51:16). The Old Testament prophets said God promised to destroy "the heavens and the earth" because Israel "broke my covenant" (Isaiah 24:5). "Heaven and earth" in the context of Isaiah's writing is not the literal heaven or the literal earth, but the Jewish economy and the Jewish age. Jesus, the apostles and the early Christians were all Jews, and they would be familiar with the "heaven and earth" language employed by prophets to describe the judgment of God on nations or ages.
The great theologian John Owen writes about Peter's prediction (pre-70 AD) in II Peter 3 regarding the end of the "heavens and earth:"
"I affirm that the heavens and earth here intended in this prophecy of Peter, the coming of the Lord, the day of judgment and perdition of ungodly men, mentioned in the destruction of that heaven and earth, do all of them relate, not to the last and final judgment of the world, but to that utter desolation and destruction that was to be made of the Judaical church and state".The early Christians clearly understood that God was coming in judgment to end "the Jewish age" (Matthew 24:3). Jesus plainly told His disciples that "not one stone" would be left upon the other at the Temple in Jerusalem. He said that "the Jewish age" would be destroyed, and He used language of the destruction of the "heavens and earth" (Matthew 24:29) as the nomenclature for the end of this Jewish age. Within a generation of Jesus speaking these words (Matthew 24:34), Jerusalem, the Temple, the age of the Jews, and the destruction of the "heavens and earth" occurred (in 70 AD), fulfilling the prophecies of Matthew 24 and Isaiah 24 regarding the end of the Jewish age. Thus, the LAW OF THE OLD COVENANT WAS ABOLISHED--precisely the way Jesus said it would be in Matthew 5:17-18, because "heaven and earth" (the Old Covenant) passed away. All the Old Testament laws (613) associated with Israel's covenant with God were now gone. Why? Because Christ had fulfilled them. He was the Anti-type, fulfilling the types. He was the Substance, predicted by the shadows. He fulfilled completely what the Law and the Prophets declared. Nobody disagrees that the idea of "the Law" passing away or being abolished, even for Christian Jews, would be a drastic change for the age in which they lived. For "the Law" to pass away means there would be no more Temple, no more feasts, no more sacrifices--the world as the Jews knew it would be forever different. But it had to pass away--because Jesus fulfilled it.
Summary: When God established His covenant with the Jews, He described it as the establishment of "heaven and earth" (Isaiah 51:16). When Israel broke their covenant with God through unfaithfulness to His Law, God described the impending judgment as the destruction of "heaven and earth" (Isaiah 24, Matthew 24, II Peter 3). The destruction of "heaven and earth" occurred in 70 AD when the Temple and the Jewish age were destroyed by the Roman army, and the "Law" was abolished, just as Jesus predicted it would be in Matthew 5:17-18.
The question then becomes, post 70 AD, what "Law" is established and in effect for Christians to follow?
Matthew presents Jesus as the New Lawgiver
(1). The early Christians saw Matthew's writings to be five books, similar to the Pentateuch of Moses.
The first book (Matthew 1-4), tells the narrative of Jesus' birth and early years and has remarkable parallels to the narratives of Israel's forefathers and Moses the Lawgiver as God led His people out of the bondage of Egypt. The second book (Matthew 5-7) parallels with the teaching of Moses on Mt. Sinai etc… as found in the book of Exodus. The third, fourth and fifth books in Matthew point us to the instructions of Jesus to His followers and parallel the teaching of Moses to Israel in the books of the law called Leviticus, Numbers and Deuteronomy.
(2). The Sermon on the Mount is preceded by baptism in water and forty days in the wilderness. Again, the whole narrative of Jesus (childhood, exodus, baptism, wilderness, mountain, law) is precisely the narrative of Moses and Israel (childhood, exodus, Red Sea, wilderness …). The parallel between Jesus' life and that of the old lawgiver Moses is clearly seen in the book of Matthew.
(3). Matthew calls Jesus greater than Moses (i.e. "hear HIM" not Moses 17:5), “greater than Solomon” (12:42), “greater than the Temple” (12:6), “greater than Jonah” (12:41), and the “Lord of the Sabbath” (12:8).
(4). It is disobedience to the Words of Christ that defines “lawlessness” (anomia) in Matthew (see 7:23-24).
(5). In the Great Commission, Jesus instructs to teach all that “I have commanded” (28:18-20).
The idea that we do not have "Law" as believers in Jesus Christ is ludicrous. Our Law is His Law. Our desire is to do His will, to hear His commands, to be His bondslaves, and to do as He bids. The Royal Law (James 2:8) of Christ is "to love one another as He has loved us" (John 13:34). Jesus, gospels writers and others of the apostles all write to help us understand how this agape love works itself out in our lives.
But now, when we read the Old Testament, we see Jesus. Our concentration is not obedience to Old Covenant "commands" or laws--we see Christ. We see Him in the narratives of creation and exodus, in the laws of sacrifice and festivals, in the prophets and the psalms--all the Old Covenant Scriptures point to Him. We, however, are not "bound" to any Old Covenant laws--including any alleged "Sabbath" day, because we are inlawed to Christ (I Corinthians 9:21). Every day is a day of rest. For those who cringe at the thought of no "Ten Commandments" for believers, we remind them that it is hard to commit adultery when you aren't lusting in your heart (Jesus' command in Matthew 5:28), or to commit murder when you don't hate (Jesus' command in Matthew 5:17), or to steal when you see a need and give to meet it (Jesus' command in Matthew 6:4), etc... It's also hard to keep any special day as a Sabbath day because every day is a day of rest in Christ (Colossians 2:16).
The Law that we follow is Christ's Law--and we willingly, cheerfully, and fully pledge ourselves to keep it as His bondslaves. But we reject any notion that our Lord's law is Moses' law. "Heaven and earth" has passed away, and a "new heaven and earth" (the New Covenant) with a new Lawgiver, a new age, a new people, and a new agreement with better promises has dawned (Hebrews 8).
In His Grace,