The law is only a shadow of the good things that are coming. It is not the real things themselves. The same sacrifices have to be offered over and over again. They must be offered year after year. That's why the law can never make perfect those who come near to worship.
References for Hebrews 10:1
If it could, wouldn't the sacrifices have stopped being offered? The worshipers would have been made clean once and for all time. They would not have felt guilty for their sins anymore.
But those offerings remind people of their sins every year.
It isn't possible for the blood of bulls and goats to take away sins.
So when Christ came into the world, he said, "You didn't want sacrifices and offerings. Instead, you prepared a body for me.
You weren't pleased with burnt offerings and sin offerings.
Then I said, 'Here I am. It is written about me in the scroll. God, I have come to do what you want.' " (Psalm 40:6-8)
First Christ said, "You didn't want sacrifices and offerings. You didn't want burnt offerings and sin offerings. You weren't pleased with them." He said that even though the law required people to bring them.
Then he said, "Here I am. I have come to do what you want." He did away with the first. He did it to put the second in place.
We have been made holy by what God wanted. We have been made holy because Jesus Christ offered his body once and for all time.
Day after day every priest stands and does his special duties. He offers the same sacrifices again and again. But they can never take away sins.
Jesus our priest offered one sacrifice for sins for all time. Then he sat down at the right hand of God.
Since that time, he waits for his enemies to be put under his control.
By that one sacrifice he has made perfect forever those who are being made holy.
The Holy Spirit also gives witness to us about this. First he says,
"This is the covenant I will make with them after that time, says the Lord. I will put my laws in their hearts. I will write my laws on their minds." (Jeremiah 31:33)
Then he adds, "I will not remember their sins anymore. I will not remember the evil things they have done." (Jeremiah 31:34)
Where those have been forgiven, there is no longer any offering for sin.