The Great Hight Priest

Since then we have a great high priest who has passed through the heavens, Jesus, the Son of God, let us hold fast our confession. (Heb. 4:14)

Question 24: How does Christ execute the office of a priest?
Answer: Christ executes the office of a priest, in his once offering up himself a sacrifice to satisfy divine justice, and to reconcile us to God, and in making continual intercession for us.

In the Old Testament only the high priest could enter into the presence of God into the Holies of Holy behind the curtain, and only then could he enter just once per year and only after having offered a sacrifice for his own sins (Heb 7:27).  This is because the high priest himself was not a perfect mediator.  He was a sinner just like the rest of us.  Not only that, but it is also made clear that all of those Old Testament sacrifices never did take away sins.  Rather the whole point of the sacrificial system was to simply remind the people, day after day, month after month, year after year, that they are sinful and in need of a a savior (Heb 10:1-4).  What the world needed was a perfect sacrifice offered by a perfect and sinless height priest who could once for all take away our sins and usher us into the presence of the living God.  Only Christ does that.  The author of Hebrews writes, "And every priest stands daily at his service, offering repeatedly the same sacrifices, which can never take away sins.  But when Christ had offered for all time a single sacrifice for sins, he sat down at the right hand of God, waiting from that time until his enemies should be made a footstool for his feet.  For by a single offering he has perfected for all time those who are being sanctified" (10:11-14).  Praise be to God we have a high priest who has done for us what no mere human could ever do--once for all atone for our sins and give us permanent access to the presence of God.