God put an end to the Law of Moses to prove that Salvation would come by His Promise and not by human works.
1. Moses never create law, so law of Moses is only nick name of the law of God.
2. Yes after cross salvation by grace, but trough faith. Now we have to have a faith to accept the grace.
Paul give example what happen to Noah to explain how to get he grace
Heb 11:7
By faith Noah, when warned about things not yet seen, in holy fear built an ark to save his family. By his faith he condemned the world and became heir of the righteousness that is in keeping with faith.
Salvation by grace through faith
In Noah case
Grace = information about : God will float the earth
Faith = He believe and build an arch
It is grace that save Noah, but it didn't mean he not work et all
His faith create thousand hour of work to build an arch
Save by grace not always mean not involve work
In our case
Grace = Jesus willing die on the cross to by our pardon
Faith = we have to trust Him to the point to love Him. And love Jesus mean love other.
1 john4:20
If a man say, I love God, and hateth his brother, he is a liar; for he that loveth not his brother whom he has seen, how can he love God whom he hath not seen?
You can't say have a faith in Jesus but hate jesus
Faith=love jesus
You can say love Jesus but hate other
Love other may create a lot of work, feed the hungry, help elderly etc. Jesus love other by sacrifice Himself on the cross, the only way we able to be like Him is if He in us and we in Him.
We not able to produce that kind of love of ourselves.
So salvation by grace doesn't mean guaranty not involve work, and professional killer don't need repent.
Salvation by grace but need love Jesus and invite Jesus into our heart
Then Jesus work on us to make us to be like Jesus, loving other and not selfish, like Him. We may not reach that level, die for other, but at least when we let Jesus come to our heart, we start go to that direction.
Once again salvation not by work, but faith, but real faith produce good fruits.