Yes for the sake of justification God’s commandments are “optional.”
How do you expect to go to Heaven?
By (A) never having committed a sin ever against God. One sin at any time in your life makes you imperfect, a sinner, and condemns you to Hell.
Considering that by this option, you are not even permitted one sin or you go to Hell, then all sin had better become “optional” in a sense. That means that God will forgive you for it. Who after even becoming a believer in Christ doesn’t need God’s forgiveness?
Or, (B) receiving God’s mercy.
Remember, the Pharisees thought they’d kept the law but even where they had, superficially, they were sinners at heart and no doubt in deed like everyone else. They thought, though, that their “good works” entitled them to Heaven (and made them morally superior to others).
Remember too, the parable of the Pharisee who commended himself to God, while the publican wouldn’t even lift His eyes to God and just begged His mercy, and it was the publican who was justified. The publican knew that no matter what, he stood guilty before God, and his only hope was to ask for God’s mercy. He didn’t tell God that he’d done this, this and this good work, but recognized due to his sin he was condemned and all he could do was throw himself on God’s mercy.
All this doesn’t mean that we aren’t to do right, though. The Bible has plenty to say on that. But we simply can’t earn our salvation by moral perfection without receiving God’s mercy.
Wrong. Justification/salvation has NEVER been a matter of law. That isn't what Torah is *for*.