Hebrews 10:1-2

Hebrews 10:1-2. For the law having a shadow of good things to come, and not the very image of the things, can never with those sacrifices which they offered year by year continually make the comers thereunto perfect. For then would they not have ceased to be offered"

If the sacrifice had really put away sin, surely it would never have needed to be offered again. If one sacrifice had put away the guilt of Israel, there would have been no need to bring another.