Messianic keepers of the law are way off base, the way I see the book of Hebrews... it was written to Hebrew Roots, Messianic types, etc. The basic theme of Hebrews is that the one to whom everything in the law pointed to had come, the new covenant (Christ) had come, rendering the old covenant no longer valid, or “dead,” dead works of the law.
The basic doctrine of Christ, is repentance from dead works, repent of it, abandon the dead works of the law, Heb. 6:1. If they claim to be some sort of Hebrew Messianic, then that’s what they must do. The book of Hebrews was written to them. Second is to have faith towards God. Faith not the works of the law.
They, of course, either don’t care what Hebrews says, or they reinterpret it to fit their desire to Judaize. Most of them claiming we are disobedient sinners because we do not keep the sabbath, observe the feasts, and so on.
I’ve seen a range of Messianics, and you can have those who seem to revert. Remember, though, that Paul did follow the religious practices of the Jews, even though there were those in his day that accused him of not following them.
That didn’t change the doctrine of Salvation, though. And the ministry to the Gentiles was given different parameters than the Jews had. We see that in Acts, when the Apostle Paul was before the Jerusalem Church
I do note that we will be keeping some of those practices, ourselves, in the 1,000 year reign of Christ, and that there will be a Temple in Jerusalem, like there was before (Ezekiel’s Temple).
Those that are not his are without his law. They despise it; they would rather spend eternity in the lake that burns than please him.
The "works of the law" speaks of the Pharisee's law (Takanot) which was hung on the cross, not Yehova's Torah.