A priest offers up sacrifices. That's what priests do.

Jesus was a high priest because He offered up Himself as sacrifice:

Hebrews 9:24 For Christ is not entered into the holy places made with hands, which are the figures of the true; but into heaven itself, now to appear in the presence of God for us:

25 Nor yet that he should offer himself often, as the high priest entereth into the holy place every year with blood of others;

26 For then must he often have suffered since the foundation of the world:

In offering up Himself Jesus simultaneously was the Lamb as well as the priest that sacrifices the Lamb.

In Revelation 13 we find that Christ, the Lamb of God, was slain at the foundation of the world:

Revelation 13:8 ...the Lamb slain from the foundation of the world.

Since Christ was slain at the foundation of the world, He also would have offered Himself up at that point. And that means He performed priestly duties at the foundation of the world.

If this were so, we would then expect to find that the Bible speaks of a priesthood different than that of Levi.

Isn't it interesting that we do find the Bible speaking of another priesthood.

And it also tells us of a mysterious high priest named Melchizedek:

Hebrews 7:1 For this Melchisedec, king of Salem, priest of the most high God, who met Abraham returning from the slaughter of the kings, and blessed him;

2 To whom also Abraham gave a tenth part of all; first being by interpretation King of righteousness, and after that also King of Salem, which is, King of peace;

3 Without father, without mother, without descent, having neither beginning of days, nor end of life; but made like unto the Son of God; abideth a priest continually.

4 Now consider how great this man was, unto whom even the patriarch Abraham gave the tenth of the spoils.

This Melchizedek is said to be of the greatest order of priests. In fact, Jesus Himself is identified as being in the SIMILITUDE of this great priest Melchizedek:

Hebrews 7:15 And it is yet far more evident: for that after the similitude of Melchisedec there ariseth another priest,

16 Who is made, not after the law of a carnal commandment, but after the power of an endless life.

17 For he testifieth, Thou art a priest for ever after the order of Melchisedec.

Yes, it's very interesting that we have TWO LAMBS SLAIN (Christ at the foundation of the world and Christ on the cross in 33 AD) and we also find that the Bible tells us of TWO HIGH PRIESTS.

Melchizedek is the first high priest. He has preeminence. Jesus, we're told is after the similitude of Melchizedek (notice how similar that sounds to a tableau), and He is also said to be after the order of Melchizedek.

Since we read about Melchizedek in Genesis chapter 14, more than two thousand years before the birth of Christ (in 7 BC), there's no question that He functioned as a priest long before Jesus did. And the chief function of a priest is to offer up sacrifice.

Hebrews 9:25 Nor yet that he should offer himself often, as the high priest entereth into the holy place every year with blood of others;

26 For then must he often have suffered since the foundation of the world:

The work of Melchizedek's priesthood was performed at the foundation of the world. That was the point in which Jesus Christ offered up Himself for the sins of His people.

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