Jesus did not simply abolish the Law of Moses. He fulfilled it by bringing its purpose to completion and revealing its deepest meaning. He taught that the central purpose of the Law is love for God and neighbor, justice, mercy, faithfulness, and a transformed heart.
If someone interrupted fulfilling the Torah as abolishing our obligation to obey it, then are interpreting that as meaning the same thing as abolishing it in spite of Jesus saying that he came to fulfill the law in contrast with saying that he came not to abolish it and in spite of him warning against relaxing the least part of it. The God of Abraham, Isaac, and Jacob has the character traits that the Torah was given in order to teach us how to embody, so its purpose is to teach us how to know, love, worship, believe in, testify about, and be one with Him through embodying His character traits, which is what Jesus taught us to do, and it still has this purpose.
Regarding “an eye for an eye,”
Jesus and the Apostles quoted from the OT hundreds of times in order to support what they were saying, so it does not work to take the position that we should follow just what they said, but not what they considered to be an authoritative source. For example, in Matthew 4, Jesus quoted three times from Deuteronomy in order to defeat the temptations of Satan, which included saying that man shall not live by bread alone but by every word that comes from the mouth of God (Deuteronomy 8:3). In Deuteronomy 12, it is a sin to add to or subtract from the Torah. In Deuteronomy 13, the way that God instructed to determine that someone is a false prophet is if they speak against obeying the Torah, so you should have major problems with you interpreting Jesus as doing that.
In Matthew 4, Jesus preceded a quote from what was written by saying "it is written...", but in Matthew 5, he preceded a quote from what the people had heard being said by saying "you have heard that it was said...", so Jesus was not sinning by making changes to what was written, but rather he was fulfilling the Torah by correcting what the people had heard being said and by teaching how to correctly obey it as it was originally intended.
Not responding in kind is in accordance with Proverbs 20:22 and 24:29. Loving our enemies is in accordance with Exodus 23:4-5, Deuteronomy 23:7, Proverbs 24:17-18, and Proverbs 25:21-22. Not hating our brother is in accordance with Leviticus 19:18. Not lusting after a married woman in our hearts is in accordance with Deuteronomy 5:18 and 21. So what Jesus was teaching was thoroughly rooted in the OT.
Jesus also restricted divorce. Moses permitted a certificate of divorce because of human hardness of heart, but Jesus restored marriage to its original purpose and treated divorce as a serious violation except in cases of sexual immorality. He rejected manipulative oath-taking and taught that a person’s ordinary “yes” and “no” should be truthful. He challenged strict Sabbath interpretations when they prevented healing, mercy, or necessary human good, saying that the Sabbath was made for humanity rather than humanity for the Sabbath.
Likewise, what Jesus taught about divorce was in accordance with the OT.
In Leviticus 19:11, it instructs to not to swear false by God's name, so someone who was following the spirit of that law would understand that we are not to swear falsely whereas someone who was following the letter of that law would understand that we are free to swear falsely just as long as we swear by something other than God's name, which is the practice that Jesus was addressing in Matthew 5:33-37.
Some of Gods laws appear to conflict, such as when God commanded to rest on the Sabbath while also commanding priests to make offerings on the Sabbath, however, it was not the case that priests were forced to sin by breaking one of the two commands no matter what they chose to do but that the lesser command was never intended to prevent us from obeying the greater command. This is why Jesus said in Matthew 12:5-7 that priests who did their duties on the Sabbath were held innocent, why David and his men were held innocent, and why Jesus defended his disciples as being innocent, so a hierarchy is part of the system. God could not have created the Sabbath until He had created everything else, which means that the creation of the Sabbath was the goal of everything else that God created first in mind and last in deed, so it is easy to see why someone might think that the Sabbath was the greatest commandment if they did not have the authority of Jesus to rely upon.
Jesus also redirected the purity laws.
The Greek words "akathartos" and "koinos" both refer to a type of impurity, but the Bible never uses them interchangeably, so it is an error to interpret the use of "koinos" in Mark 7 and Matthew 15 as if Jesus had said "akathartos" instead. Jesus was having a conversation about whether we can become common (koinos) by eating bread with unwashed hands (Matthew 15:20), so he was not even speaking about eating animals or about what kinds of things we are permitted to eat. Again, you should have major problems with interpreting Jesus as speaking against obeying what God spoke in Deuteronomy 14 in regard to refraining from acting unclean animals. Jesus said that if we are making an offering and remember that our brother has something against us, then we should go make peace with our brother, then return to make the offering, so he emphasized our relationship wth our neighbor, but said nothing to diminish making an offering.
Some parts of the Mosaic covenant cannot be applied as binding laws in the new-covenant era because they belonged specifically to Israel’s covenant, priesthood, temple, and national system. These include animal sacrifices, the Levitical priesthood, temple regulations, ritual washings, circumcision as a covenant requirement, food restrictions, distinctions between clean and unclean animals, rules concerning ritual impurity, Israel’s festivals and sacred calendar as conditions of membership, and civil penalties administered by Israel’s national government.
While it is true that there are laws in regard to Temple practice that we can't practice without the Temple, that does not mean that we should not obey the Torah to the extent that we are able to obey. In 1 Peter 1:16, we are told to be holy for God is holy, which is a quote from Leviticus where God was giving instructions for how to do that, which includes keeping His Sabbaths holy (Leviticus 11:44-45) and refraining from eating unclean animals (Leviticus 11:44-45). In 1 Peter 2:9-10, Gentiles are included as part of God's chose people, a holy nation, a royal priesthood, and a treasure of God's own possession, which are terms used to describe Israel (Deuteronomy 7:6), so Gentiles also get to obey the instructions that God gave for how to fulfill those roles. It would be contradictory for a Gentile to want to live as part of a holy nation while wanting nothing to do with following God's instructions for how to live as part of a holy nation. If our goal is to embody God's character traits, then the only way that we should cease to obey God's instructions for how to be holy as He is holy would be if He were to cease to be holy. There are also many other verses that call for Gentiles to be holy, so holiness is not just for Jews.
The animal sacrifices pointed forward to the final offering of Christ
The sacrificial system always pointed to Christ and we should live in a way that points towards him by obeying the Torah rather than a way that points away from him. In Acts 21:20-24, they planned to pay for the offerings of people who had taken a vow in order to disprove false rumors that Paul had been teaching against obeying the Torah and to show that he continued to live in obedience to it. In Hebrews 8:4, it refers to offerings that were still being done in accordance with the Torah, so offerings did not cease with the death or resurrection of Jesus but only ceased because of the destruction of the Temple. A priesthood led by God's Word made flesh does not involve departing from God's Word. The New Covenant still involves following the Torah (Jeremiah 31:33).
The continuing significance of the Law is therefore found not in reproducing Israel’s ritual and national system, but in understanding the holiness, justice, mercy, and love to which those laws pointed. Jesus deepened the moral commands, fulfilled the symbolic laws, and established the new covenant through himself: “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them” (Matthew 5:17).
The purpose of God's Word being made flesh is to lead us to embody God's Word, not to lead us away from doing that.