To piggyback on what KohenMatt has said about context, I'd like to share an modern day example [with scripture context].
---Scene 1---
I'm speeding down the highway and get stopped by a state trooper.
He tells me I've been caught traveling just 10mph over the speed limit and gives me a $300k ticket. What are my options at this point?
Can I tell the officer that I'll personally travel at the speed limit from now on to ***undo** the ticket?
No, of course not. I've already been caught; already guilty of breaking the law. So following the speed limit now can't "un-guilt" me & make me right(eous) or just(ified) again in the law's eye. I can't follow the law, in my guilty state, to restore my own good standing (i.e. make me righteous or justified). The ticket can't be unmade by anything I do to obey the speeding law after breaking it. Obeying the law, **as a guilty person**, can't save me from the debt of the ticket I owe. It must be paid.
[^The proper context of Galatians 2:16: "a person is not justified by the works of the law"]
So I have to **remedy** my crime either by:
A) Paying the ticket myself, or
B) Receive mercy from the court: they forgive my crime and get someone else to pay my ticket
---Scene 2---
I go to court and confess to the judge that I was speeding, but then say I can't pay the fine. At $300k, the price is too high; can't afford it. The consequence is I'll be put in prison if I don't pay so I beg for forgiveness.
My attorney (the judge's son), having compassion on me, pulls out his checkbook and writes a check for the amount I owe.
I say, "thank you for saving me from the judgement!!" There was nothing I could do to pay my ticket and avoid judgment. I was completely at the mercy of the judge and without the compassion of my attorney I would've faced that judgment. He alone paid the price for me and the judge declared me right(eous) again in the eyes of the speeding law. The law has been satisfied by my attorney so that my record is clean. I am justified; no longer guilty.
[^The proper context of Galatians 2:21 & Ephesians 2:8: "salvation from Christ alone who paid my price. I am justified, not of my effort or any work of the law I could do."]
---Scene 3---
Now before I leave my attorney tells me "go and speed no more". The judge then adds, "My son is also a driving instructor and I'm making him available to you. He'll be with you to teach you how to properly obey the driving law so that you speed no more."
I leave the court side by side with my attorney who's now my driving instructor, free and clear from the judgment. He and I approach my car, with me once again right(eous) in the law's eye; made just(ified) by the attorney's free gift.
[^The proper context of Ezekiel 36:27, Malachi 3:2, John 16:13, Philippians 4:13: "I will put my spirit in you and move you to follow my decrees & laws. He will refine the priests of God so they worship in righteousness. The spirit of truth will guide you. I can do all things through Christ who gives me strength"]
So now I have a choice to make from this point forward:
A) Obey the speed limit to "speed no more", or
B) Do not obey the speed limit
---Scene 4---
Before we leave, two friends approach me who were in the court with me...
One of my friends says, "Great! Make sure you obey the speed limit from now on so you're not found guilty of it again. PLUS...The judge gave you his son to drive with you and instruct you on how to obey the law properly from now on. But if your car is caught speeding again, it's ok. Your driving instructor is your attorney so he'll cover you. But I hear he's the best driving instructor ever. His lessons are perfect, so eventually you should never break the speeding law again."
[^The proper context of John 8:11, Matthew 19:17, Romans 8:2, 1 John 1:9, James 1:25 & James 2:14-26: "Go and sin no more (after being forgiven & justified). Obey the commandments (after being made righteous). No longer slave to sin (in Christ). The spirit of truth (guides proper obedience). law of spirit & life (over condemnation). the spirit over the letter (gives life). Faith without works is dead. If we confess our sins he's faithful and just to forgive."]
...
However another friend says, "No, no, no. You can't obey the speed limit at all because if you did you would be rejecting your attorney's gift...and you'll owe the original $300k if ever you tried to. Obeying the speed limit can't make you right(eous) in the law's eye. No, you're actually incapable of obeying the driving law...So just accept the son's gift.
You can't stop speeding even if you wanted to, not until you're given a new car. In fact, you're not allowed to drive anymore. Let your driving instructor drive you wherever you need to go...because once you get behind the wheel you'll automatically fail. Just let him do all of the work; there's no work required on your part.
And each time your car gets a speeding ticket - because you *will* get more speeding tickets (even though your driving instructor is behind the wheel) - He'll cover you again and again until he finally buys you that new car you need that'll make all the difference."
Which friend gives the correct advice? Whose advice makes sense? What does your spirit tell you?
---End---
In my example, my second friend misunderstands the context of how becoming right(eous) and just(ified), through no act of oneself, is separate from obeying the law which is still required to be followed. He doesn't understand, if my guilt was settled outside of my obedience to the speeding law, how I can go back to obeying the speed limit and it not undo everything. He's not seeing both sides of the law; getting hung up on the remedy (section above in purple).
There are two (2) parts to every law in existence:
1) The command *to avoid* a crime (and remain just/right/good)
2) The remedy *to pay for* the crime (and restore a just/right/good standing)
When a person fails to follow part 1 of a law and is found guilty, they can't continue to follow part 1 to "unguilt" themselves. They need to follow part 2 to restore their good standing (righteousness). But once they are right again, they can return to following part 1, and are indeed encouraged to by *every* authority (both in the natural and heavenly). So in my example the speeding law is:
1) Command: Travel at the posted speed limit
2) Remedy: Pay $300k speeding ticket or be jailed for a time
And in the case of sin, God's law says:
1) Command: Do not sin
2) Remedy: There must be a death; a life but be paid
See that both parts are equally the law...so we can call the command "the law" and the remedy "the law", we just need to know which is being referred to in context.
Now when someone sins, God's law (i.e. the remedy) says there has to be a death, but killing animals in a ritual was ***always*** a placeholder. It's insufficient to do the real job of making one right again; it's just an example to explain what Christ would do with his blood.
Now no one has ever seen Christ perform this act of sprinkling his blood to cleans because it was/is done in heaven. So it takes faith alone to believe Christ has made us right and just, saving us from the judgment of death. Saved by Christ's grace, through faith (because we can't see him in heaven performing this work). Faith is the evidence of things not seen. Christ's act fulfilled/satisfied part 2 of the law; the remedy.
HOWEVER...
AFTER one is made right again, and is forgiven by Christ he repeats the words "sin no more". In other words, part 2 was satisfied/fulfilled by him alone so we are expected to return to part 1: performing the works of a right(eous) man and woman (i.e. obeying the commandments).
But we're not left alone in this task because we're ALSO given Christ's Holy Spirit to teach us how to properly obey the commandments so that we don't misinterpret the letters of part 1 and instead follow the spirit of part 1 in proper context. Then if we stumble in our walk towards perfection Christ is still ministering in heaven on our behalf, satisfying part 2.
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Forgive me for the length but I encourage rereading my example a few times to understand the dynamics of the law and grace in context. I feel it's important to avoid misunderstanding the nuances.