Another seemingly common misunderstanding from Paul is that people think he says we must not keep the law, and if we keep it Messiah died in vain.. He never said/meant that!;
Galatians 2:21 "I do not make void the grace of Elohim, for if righteousness is through the law, then Messiah died in vain"
Quick Answer: This does not mean if you obey commandments then you're making void the grace of Elohim. This is simply stating a fact that if it was possible for us to be righteous through the law then there would be no need for the Messiah to be a sacrifice that grants us pardoning and righteousness. We can't become perfectly righteous in the sight of Elohim by the law because we have broken it. It's not saying stop keeping commandments, the subject is we can't be saved by the law and declared totally righteous.
It is ridiculous that people are actually using these out of context and telling people stop obeying the law as if they're doing something wrong by doing what the creator told us to do.
What do they think is going to happen when people quit obeying righteous instructions? What is there to gain from that?
So to get right into it, if we could become righteous from the law then indeed we didn't need Messiah and he died in vain.
Paul is simply stating the fact that we can not obtain perfect righteousness through the law and the keeping of commandments because all of us have sinned at least once keeping us from being declared totally righteous, we can not keep the law perfectly always and this is why we needed a savior, and thanks be to YHWH who saved us through Yahushua the Messiah!(1 Corinthians 15:57)
We must realize that is what Paul meant, and he is not saying anything about if we keep the commandments we're making void the grace of Elohim.
If we reject the free gift of righteousness given to us by YHWH, and say we're going to try to get that righteousness a different way, then we are making void his grace(grace means something like loving kindness).
The pharisees were known to be teaching people that they could obtain righteousness through the law, and they were rejecting the free gift of pardoning through Yahushua the Messiah, this is a very important teaching for people like that.
Now, the truth is if we do not try to keep the law to the best of our ability, then Messiah died in vain for us!
So the Truth is opposite to the common misunderstanding and teaching!;
Hebrews 10:26 "For if we go on sinning deliberately after receiving the knowledge of the truth, there no longer remains a sacrifice for sins"