There was never any sacrifice for willful sin, that is, doing sin when we know it is sin, such as casting aside the 4th Commandment, which BTW, is the Day in which He placed His Name, the Day that Christ is the Master of.
Grace has been from the beginning in the very first sacrifice God made when He killed a lamb to cover the sins of Adam & Eve. And then they took that covering with them as they left the garden and they taught their children the importance of that sacrificed lamb and the importance of bringing that sacrifice before God. Both Cain & Abel knew the importance of the lamb, however Cain denied it by his failure to bring the proper sin offering. And that is why Jesus said,
John 3:36 Whoever believes in the Son has eternal life; whoever does not obey the Son shall not see life, but the wrath of God remains on him.
His commandments are not hard. What is hard is all the crap that the religious elite added to them and that is what Christ freed us from, the extra burdens that man had placed on the commandments of God.
And so it is, those who say they are of Christ, yet reject the day of gathering together for His instruction, they have no clue as to the enormous amount of patience God has. As far as His grace in this matter, well, looking at the physical health of the bodies of those and how sick they are, dying of gruesome diseases, I do not see grace, I see the curses that the Word of God instructed Moses to write down. I see that lack of faith in that the Gospel says that Christ carried ALL of our sicknesses and diseases so that we should not be burdened with them.
And that is why we have chosen to separate ourselves from that religious system that rejects the authority of Christ in their daily lives, especially the need to stop once a week, on His appointed Sabbath day by removing ourselves from the system of commerce so to be a light to the nations, that the inhabitants of those nations would too come to Christ so to receive the blessings of His instructions. Shalom
Mark 2:27-3:4
27
Then he said to them, "The Sabbath was made for man, not man for the Sabbath. 28 So the Son of Man is Lord even of the Sabbath."3
Another time he went into the synagogue, and a man with a shriveled hand was there. 2 Some of them were looking for a reason to accuse Jesus, so they watched him closely to see if he would heal him on the Sabbath. 3 Jesus said to the man with the shriveled hand, "Stand up in front of everyone."4
Then Jesus asked them, "Which is lawful on the Sabbath: to do good or to do evil, to save life or to kill?" But they remained silent.
NIV