I agree, Christ is the end of the law and Paul clearly proclaims that. Here Paul is not reminding them of the OT commandments.
Those are the same commandments, and they have the same purpose. "You know the commandments...", Paul is reminding them of what they are....
If we look at the rest of the verse, we see where the commandments came from
1 Thes. 4:2
for you know what commandments we gave you through the Lord Jesus.
These are not the commandments from Moses. Also, if we look at the prior verse again it says its’ from them,
4:1
Finally then, brethren, we urge and exhort in the Lord Jesus that you should abound more and more, just as you received from us how you ought to walk and to please God;
Paul says the things he writes are commandments from Christ.
1 Cor. 14:37
If anyone thinks himself to be a prophet or spiritual, let him acknowledge that the things which I write to you are the commandments of the Lord.
As far as the vine, it isn't like the body, because we can never be "severed" from Christ.
You should check your translation on "severed". Paul specifically speaks of those who are "justified by the law".
I checked the word, thanks. Here it is. Sever is one of the definitions.
katargeó: to render inoperative, abolish
Original Word: καταργέω
Part of Speech: Verb
Transliteration: katargeó
Phonetic Spelling: (kat-arg-eh'-o)
Short Definition: I bring to naught, sever, abolish
Definition: (a) I make idle (inactive), make of no effect, annul, abolish, bring to naught, (b) I discharge, sever, separate from.
They have fallen from grace, because grace can only be accessed through faith.
I agree. That is what this book is about. Men were trying to add circumcision to the gospel.
If we look at the context of chapter 5, these Christians were influenced to add circumcision, but Paul tells them not to go back to it and if they do they need to keep the whole law and Christ will be no good to them for the will fall from grace.
NKJV
5:1
Stand fast therefore in the liberty by which Christ has made us free, and do not be entangled again with a yoke of bondage. 2 Indeed I, Paul, say to you that if you become circumcised, Christ will profit you nothing. 3 And I testify again to every man who becomes circumcised that he is a debtor to keep the whole law. 4 You have become estranged from Christ, you who attempt to be justified by law; you have fallen from grace.
It’s clear. It’s Christ or the old law, you can’t have both. One saves and the other does not.
Galatians 2:21 I do not frustrate the grace of God: for if righteousness come by the law, then Christ is dead in vain.
All those who attempt to access grace through their own obedience frustrate the grace of God..."then Christ is dead in vain."
He’s not talking about their obedience; he’s talking about trying to be righteous under that old law something they have done their whole life.
Anyway, that’s how I understand it.