From “How to become a Christian”: Chapter 10 – Jesus’s death on the cross
This feast, ‘the Day of Atonement’, came only once a year. On this special day, and only on this day, the Jewish High Priest was allowed to go into the very most holy part of the Temple, the Holy of Holies. Once in there he would take some of the blood of a lamb which had been sacrificed and sprinkle it on what was called the ‘mercy seat’. This was to ‘cover for’ the sins of the Jewish people for another year.
The actions of the High Priest on the day of atonement were yet another illustration or ‘type’ or what Jesus would later do for us. However, even this could not fully take sins away; it could only temporarily cover them, for one year, not permanently:
“Aaron shall make atonement on its horns once a year; he shall make atonement on it with the blood of the sin offering of atonement once a year throughout your generations. It is most holy to the LORD.”Exodus 30:10 (NASB)
The writer of the letter to the Hebrews in the New Testament refers to this very important concept of the Day of Atonement and the sacrifice made by the Jewish High Priest. It illustrates and explains what Jesus Christ did on our behalf:
24For Christ did not enter a man-made sanctuary that was only a copy of the true one; he entered heaven itself, now to appear for us in God’s presence. 25Nor did he enter heaven to offer himself again and again, the way the high priest enters the Most Holy Place every year with blood that is not his own. 26Then Christ would have had to suffer many times since the creation of the world. But now he has appeared once for all at the end of the ages to do away with sin by the sacrifice of himself.Hebrews 9:24-26 (NIV)
This is quite a complex passage but, basically, it explains that what Jesus did when He died for us on the cross was similar to what the Jewish High Priest did each year in sacrificing animals to cover for the sins of the people. The crucial difference was that Jesus’ sacrifice of Himself and the shedding of His own blood was a perfect and permanent sacrifice. What had gone on before in the Temple was only a shadow or forerunner of what He would later do. Whereas the sacrifice of the animals in the Jewish Temple had to be done over and over again, the perfect sacrifice of Jesus, the sinless Lamb of God, only had to be done once. That was enough to save all people, however many, and wherever and whenever they live:
10By this will we have been sanctified through the offering of the body of Jesus Christ once for all. 11Every priest stands daily ministering and offering time after time the same sacrifices, which can never take away sins; 12but He, having offered one sacrifice for sins for all time, sat down at the right hand of God,Hebrews 10:10-12 (NASB)
In doing what He did, Jesus was playing the part of both the High Priest and the sacrificed lamb. He was the one making the offering and He was also the offering itself. Whereas the High Priest made an offering of a lamb and sacrificed it, Jesus offered Himself. So, having offered the perfect sacrifice of Himself, and having been raised from the dead, Jesus’ task was done. He will never need to die for us again. Instead, He was able to sit down in the place of honour at the right hand of God the Father, because His task of paying for our sins was complete.