A shadow of the Christ to come
The High Priest
When Israel needed someone to stand between them and God, they looked to the high priest. Aaron, brother of Moses, was the first, robed in blue and gold, a breastplate of twelve stones over his heart, the names of the tribes carried into the sanctuary. His office was weighty and personal. He offered the sacrifices, entered the holy place, and once a year passed behind the veil on the Day of Atonement to make peace for the whole nation. He bore the people's needs before God and God's holiness before the people. Yet Aaron was himself a sinner, needing to offer for his own sins before he could offer for theirs, and every high priest after him grew old and died, so the office passed from one mortal man to the next, never finished, always in need of another.
“Seeing then that we have a great high priest, that is passed into the heavens, Jesus the Son of God, let us hold fast our profession.”Hebrews 4:14
“For we have not an high priest which cannot be touched with the feeling of our infirmities; but was in all points tempted like as we are, yet without sin.”Hebrews 4:15
“Wherefore he is able also to save them to the uttermost that come unto God by him, seeing he ever liveth to make intercession for them.”Hebrews 7:25
The shadow, in its own place
The high priesthood was a real and central institution in Israel. The high priest represented the whole nation before God, offering sacrifices, teaching the law, and above all making atonement. He wore garments loaded with meaning: the names of the tribes on his shoulders and heart, so that he carried the people into God's presence. His work maintained the covenant relationship, dealing with the sin that would otherwise separate God from His own. But the office bore its own limits within it. The high priest was mortal and sinful, needing cleansing himself. He could not remove death or fully cleanse the conscience. Generation after generation, the priesthood continued only because each priest in turn died and had to be replaced by another.
The pattern it traces
The shape is mediation and intercession: one appointed to stand between the holy God and a sinful people, to represent them before Him and offer for their sin. The priest sympathizes with the people because he shares their weakness, and he pleads their cause before God. Yet the pattern is stamped everywhere with insufficiency. The priests died and were replaced. They sinned and needed atonement themselves. Their sacrifices were repeated endlessly because none could finally take sin away. The pattern of the mediating priest therefore leans forward, longing for a priest who does not sin, who does not die, whose single offering suffices, and who lives on to keep interceding for those he represents.
How it is fulfilled in Christ
Hebrews gives the fulfillment its clearest voice. In its fourth chapter it names Jesus a great high priest who has passed into the heavens, one who sympathizes with our weaknesses because He was tempted in every way as we are, yet without sin. Where Aaron entered a curtained room once a year, Jesus has entered heaven itself. Where Aaron offered for his own sins first, Jesus, being sinless, offered only for ours, and offered Himself. And Hebrews adds, in its seventh chapter, that because He lives forever His priesthood does not pass to another; He is able to save completely those who come to God through Him, since He always lives to make intercession for them. The office that could never rest in mortal hands rests forever in the risen Christ.
Questions people ask
How can Jesus be both the priest and the sacrifice?
In the old system the priest and the offering were separate; the priest presented an animal. Christ unites the two. As priest He represents us before God, and as offering He gives His own life for our sin. Hebrews presents this as the reason His work is final: He did not bring another creature's blood but offered Himself, once and completely.
Why does it matter that Jesus 'ever lives to intercede'?
Every earthly high priest eventually died, so the office kept passing to someone else and the work was never finished. Because the risen Christ never dies, His priesthood never passes on and His intercession never stops. Hebrews draws the comfort from this: He is able to save fully and forever those who come to God through Him, because He is always alive to pray for them.