For since the law has but a shadow of the good things to come instead of the true form of these realities, it can never, by the same sacrifices that are continually offered every year, make perfect those who draw near. Otherwise, would they not have ceased to be offered, since the worshipers, having once been cleansed, would no longer have any consciousness of sins? But in these sacrifices there is a reminder of sins every year. For it is impossible for the blood of bulls and goats to take away sins.
Consequently, when Christ came into the world, he said,
“Sacrifices and offerings you have not desired, but a body have you prepared for me; in burnt offerings and sin offerings you have taken no pleasure. Then I said, ‘Behold, I have come to do your will, O God, as it is written of me in the scroll of the book.’”
When he said above, “You have neither desired nor taken pleasure in sacrifices and offerings and burnt offerings and sin offerings” (these are offered according to the law), then he added, “Behold, I have come to do your will.” He does away with the first in order to establish the second. And by that will we have been sanctified through the offering of the body of Jesus Christ once for all. (Hebrews 10:1-10, ESV)
If you were king David and you had come near to being extinguished in war only to find the God you trusted and worshiped bring you an astonishing victory, it would have been most appropriate for you to bring a sacrifice, a freewill offering, to Yahweh and invite others to a banquet to give testimony to God’s deliverance. David did this often.
But in Psalm 40, which our author quotes here, David does something different. Not that he won’t bring a sacrifice, but he teaches something most important, that God’s greatest desire is doing His will. If I bring a sacrifice but don’t have a heart of worship God will not be pleased. David has come to do God’s will as it is written in the law.
The author of Hebrews quotes this passage because he has already deduced from the annual ceremony of the Day of Atonement and the use of animals as sacrifices that this is not God’s permanent means of providing cleansing from a consciousness of sins. Otherwise they would not have to be offered over and over. And it should be self-evident that animals cannot be adequate substitutes for humans.
Jesus as Messiah is the fulfillment of David’s kingship. He is the ultimate “David” who has come to do God’s will. His body is that ultimate sacrifice that God desires. This congregation that is considering leaving Christ is leaving the fulfillment, the true reality, for its shadow. They’re going back to what has been done away with and leaving the good things the law anticipated.
What about you? Have you experienced just how good and real life in Jesus Christ is? Or are you still living in the shadows?