Jesus was the fulfillment of the old laws as they were in preparation of His coming. And it depends what law Jesus was referring to. In John 8 He literally stopped a stoning which would have been justified under said law.
As Jesus said: Matthew 22:37-40 ESV
[37] And he said to him, “You shall love the Lord your God with all your heart and with all your soul and with all your mind. [38] This is the great and first commandment. [39] And a second is like it: You shall love your neighbor as yourself. [40] On these two commandments depend all the Law and the Prophets.”
and St Paul also wrote about this:
Galatians 3:15-29 ESV
[15] To give a human example, brothers: even with a man-made covenant, no one annuls it or adds to it once it has been ratified. [16] Now the promises were made to Abraham and to his offspring. It does not say, “And to offsprings,” referring to many, but referring to one, “And to your offspring,” who is Christ. [17] This is what I mean: the law, which came 430 years afterward, does not annul a covenant previously ratified by God, so as to make the promise void. [18] For if the inheritance comes by the law, it no longer comes by promise; but God gave it to Abraham by a promise. [19] Why then the law? It was added because of transgressions, until the offspring should come to whom the promise had been made, and it was put in place through angels by an intermediary. [20] Now an intermediary implies more than one, but God is one. [21] Is the law then contrary to the promises of God? Certainly not! For if a law had been given that could give life, then righteousness would indeed be by the law. [22] But the Scripture imprisoned everything under sin, so that the promise by faith in Jesus Christ might be given to those who believe. [23] Now before faith came, we were held captive under the law, imprisoned until the coming faith would be revealed. [24] So then, the law was our guardian until Christ came, in order that we might be justified by faith. [25] But now that faith has come, we are no longer under a guardian, [26] for in Christ Jesus you are all sons of God, through faith. [27] For as many of you as were baptized into Christ have put on Christ. [28] There is neither Jew nor Greek, there is neither slave nor free, there is no male and female, for you are all one in Christ Jesus. [29] And if you are Christ’s, then you are Abraham’s offspring, heirs according to promise.
Christianity - The Gospel is Good News. As we are free from this law through Christ. And we can be freed from our sin.
Catholics and Orthodox, despite being ecclesiastical, still recognise Protestants as Christians even if lesser Christians. Oneness pentecostals aren’t considered Christians either. Denying the trinity is weirdly enough the first sign of being a cult.