I wasn't questioning your motives, but merely making a suggestion.
Personally, I believe that the epistle to the Hebrews is a major key towards understanding this whole "law vs. grace" thing.
In that epistle, we see Christ FULFILLING a lot of Old Testament types as the true antitype.
For example, he is the true sacrifice that all of the Old Testament sacrifices pointed to, and, therefore, they no longer need to be offered.
However, when it comes to certain commandments themselves, what the prophet Jeremiah wrote in Jeremiah 31:31-34 is twice quoted.
I'm referring, of course, to the following:
Hebrews chapter 8
[7] For if that first covenant had been faultless, then should no place have been sought for the second.
[8] For finding fault with them, he saith, Behold, the days come, saith the Lord, when I will make a new covenant with the house of Israel and with the house of Judah:
[9] Not according to the covenant that I made with their fathers in the day when I took them by the hand to lead them out of the land of Egypt; because they continued not in my covenant, and I regarded them not, saith the Lord.
[10] For this is the covenant that I will make with the house of Israel after those days, saith the Lord; I will put my laws into their mind, and write them in their hearts: and I will be to them a God, and they shall be to me a people:
[11] And they shall not teach every man his neighbour, and every man his brother, saying, Know the Lord: for all shall know me, from the least to the greatest.
[12] For I will be merciful to their unrighteousness, and their sins and their iniquities will I remember no more.
[13] In that he saith, A new covenant, he hath made the first old. Now that which decayeth and waxeth old is ready to vanish away.
This "new covenant" which is replacing "that which decays and waxes old" and "is ready to vanish away" does NOT remove certain of God's commandments. Instead, it transfers them from tables of stone to our minds and our hearts.
Again:
Hebrews chapter 10
[15] Whereof the Holy Ghost also is a witness to us: for after that he had said before,
[16] This is the covenant that I will make with them after those days, saith the Lord, I will put my laws into their hearts, and in their minds will I write them;
[17] And their sins and iniquities will I remember no more.
This transference of God's commandments from outward tables of stone to fleshy tables of our hearts perfectly coincides with what Paul said to the saints at Corinth.
II Corinthians chapter 3
[2] Ye are our epistle written in our hearts, known and read of all men:
[3] Forasmuch as ye are manifestly declared to be the epistle of Christ ministered by us, written not with ink, but with the Spirit of the living God; not in tables of stone, but in fleshy tables of the heart.
Furthermore, if perfectly coincides with what Jesus went on to say in Matthew chapter 5.
We read:
Matthew chapter 5
[17] Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil.
[18] For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled.
[19] Whosoever therefore shall break one of these least commandments, and shall teach men so, he shall be called the least in the kingdom of heaven: but whosoever shall do and teach them, the same shall be called great in the kingdom of heaven.
[20] For I say unto you, That except your righteousness shall exceed the righteousness of the scribes and Pharisees, ye shall in no case enter into the kingdom of heaven.
[21] 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:
[22] 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.
[23] Therefore if thou bring thy gift to the altar, and there rememberest that thy brother hath ought against thee;
[24] Leave there thy gift before the altar, and go thy way; first be reconciled to thy brother, and then come and offer thy gift.
[25] Agree with thine adversary quickly, whiles thou art in the way with him; lest at any time the adversary deliver thee to the judge, and the judge deliver thee to the officer, and thou be cast into prison.
[26] Verily I say unto thee, Thou shalt by no means come out thence, till thou hast paid the uttermost farthing.
[27] Ye have heard that it was said by them of old time, Thou shalt not commit adultery:
[28] But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart.
[29] And if thy right eye offend thee, pluck it out, and cast it from thee: for it is profitable for thee that one of thy members should perish, and not that thy whole body should be cast into hell.
[30] And if thy right hand offend thee, cut if off, and cast it from thee: for it is profitable for thee that one of thy members should perish, and not that thy whole body should be cast into hell.
Here, Jesus twice contrasts what "was said by them of old time" or the law of Moses with "but I say unto you" or how it will be under the New Covenant. Under the Old Covenant, someone had to literally murder or commit adultery in order to be guilty. Under the New Covenant, it's a matter of the heart, and not just a matter of an outward act or deed.
As Christians, are we free to steal?
Are we free to covet?
Are we free to bow to idols?
There are plenty of warnings against the same throughout the New Testament.
Similarly, there are several places in the New Testament (including what I previously quoted from Ephesians chapter 6) where an Old Testament commandment is presented to New Testament saints as doctrine.
With such being the case, I don't see any disharmony whatsoever between what both Jesus and Paul actually said.