The people of God in the Old Testament would have to go before the high priest of that time to receive forgiveness and cleansing of their sins. They went before fallible men, who themselves needed to be cleansed. The high priest received cleansing by sacrifice as well. All this by the law that was given to them, telling the how to be cleansed.

Then came Jesus, who became the High Priest, not by lineage, but by appointment from God through a new oath. This new High Priest was able to forgive sins without having to be cleansed first. His forgiveness did not come from law, but from the offering He paid himself for the atonement of all.

What greater sacrifice is needed? There is none, and if we as Christians believe that Jesus paid that price for our lives before we even knew about it and accepted him, how much more should we strive to give him our lives as a offering of thanksgiving for what he has done.

Hebrews 7:22-28