While I would normally agree with much of what you write, and understand in part where you are coming from, the writer of Hebrews links Christ's death and sacrifice with the following:
Day after day every priest stands and performs his religious duties; again and again he offers the same sacrifices, which can never take away sins. [SUP]
12 [/SUP]But when this priest had offered for all time one sacrifice for sins, he sat down at the right hand of God, [SUP]
13 [/SUP]and since that time he waits for his enemies to be made his footstool. [SUP]
14 [/SUP]For by one sacrifice he has made perfect forever those who are being made holy.[SUP]
15 [/SUP]The Holy Spirit also testifies to us about this. First he says:
[SUP]
16 [/SUP]“
This is the covenant I will make with them
after that time, says the Lord.
I will put my laws in their hearts,
and I will write them on their minds.”[SUP]
[b][/SUP]
[SUP]
17 [/SUP]Then he adds:
“Their sins and lawless acts
I will remember no more
Heb 10:9-16
Both parts are included, not just one.
If the law God desires a person to keep is not written on their mind and placed on their heart, they have a licence to sin, for their sins and lawless deeds will be remembered no more