Sin is lawlessness, without law, disobedience, disagreement with God like in the case study of the disagreement unto sin of Adam and Eve, condonation of sin. Thus, the Law of Moses cannot be abolished because it sets what God disagrees with, as displeasing behaviors and what He commands us to do, since the inception of His will in the wilderness, which is the same till the end of our world.

Everyone who is doing sin is doing lawlessness also, and sin is lawlessness." 1 John 3:4 CLV

Whenever we find any disagreement in Moses and the Prophets, disagreement which has nothing to do with the fulfilled works of the Law in Moses, we are sinning, just as Moses did, only or rather simply by even not following the instructions of Yehoshua (Jesus) to speak and not to strike the rock, a simple matter.

Remember, also, that Uzzah died for not following the instruction or the commandment of God, even though he had a good intention (2 Samuel 6:5-10).

According to 1 John 3:4, sin is lawlessness (we do not follow the law for whatever reason).
The Law contains requests from God such as holiness (sanctification), the keeping of the sabbath (rest) day, the loving of one another, et al. The Law also contains laws against what we believe and our behaviors which God rebuke.

We sin when we disregard the requests of God in the Law or when we disregard the beliefs and the behaviors that God deems displeasing to Him. In other words, we sin when we disobey God or disagree with Him in anything.

We know that God condemns homosexuality (Romans 1:18-32). But upon seeing how homosexuals love each other, more than yourself has been loved or loved, your heart got pricked into asking yourself how could homosexual love be wrong in the eyes of God if all they do is love each other. If we disagree with God upon what He deems a sin or endorses (Greek, think well with) a sin, we sin (Romans 1:32).

Also, condoning the sin of a brother of the same belief is a sin (1 Corinthians 5, 1 Timothy 5:20).
If we believe and teach that there is no law with Jesus or that one law or commandment is no more, we have been misguided by the disguised agents of the disguised messenger of light (Satan), because the Law of Moses is the will of God that YHWH (Jesus) gave to Moses to TEACH, a will which can never be added to, can never be diminished, nor even interpreted, according to Deuteronomy 4:1-2, 5:31-32.

Logically, God has not abolished any sin (disobedience) or any law, except where we read the expression "Ye have heard that it hath been said, An eye for an eye, and a tooth for a tooth, but I say". Matthew 5:38 KJV

Whoever discourses against the keeping of any law or command in Moses, they assume the authority to abolish the will of God and, as such, they must be disguised ministers of light of Satan, as spoken of in 2 Corinthians 11:14-15.

Whoever discourses against any law or command in Moses is teaching the classical lie of the serpent 'Ye shall not die' because of the principle of James 2:10.

Yet, there is a sin, an unrighteousness which does not lead to death. What is that kind of sin? The Greek of the New Testament identifies it as 'adikia' with its connotation in Greek mythology.
All unrighteousness [ἀδικία] is sin: and there is a sin not unto death. 1 John 5:17 ASV

If anyone should be perceiving his brother sinning a sin not to death, he shall be requesting, and He will be giving him life for those sinning not to death. There is a sin to death: I am not saying that he should be asking concerning that." 1 John 5:16 CLV

All injustice (adikia, wrong, beating) sin is and is sin not toward death." 1 John 5:17 CESAIRE

2 Corinthians 11:14-15 ASV
(14)  And no marvel; for even Satan fashioneth himself into an angel of light.
(15)  It is no great thing therefore if his ministers also fashion themselves as ministers of righteousness, whose end shall be according to their works.