"And Melchizedek king of Salem brought forth bread and wine: and he was the priest of the  most high God." Genesis 14:18

Who was this mystical figure named Melchizedek? There is one mention of Melchizedek in the Old Testament as quoted above in Genesis 14. He is also mentioned once in the middle of the Bible in Psalms 110:4, and finally once in the New Testament book of Hebrew.  Hebrews 7 offers the most accurate description of this mystical priest/king --

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 have the tenth of the spoils.
5 And verily they that are of the sons of Levi, who receive the office of the priesthood, have a commandment to take tithes of the people according to the law, that is, of their brethren,               
6 But he whose descent is not counted from them received tithes of Abraham, and blessed him that had the promises.
7 And without all contradiction the less is blessed of the better.
8 And here men that die receive tithes; but there he receiveth them, of whom it is witnessed that he liveth.
9 And as I may so say, Levi also, who receiveth tithes, payed tithes in Abraham.
10 For he was yet in the loins of his father, when Melchisedec met him.
11 If therefore perfection were by the Levitical priesthood, (for under it the people received the law,) what further need was there that another priest should rise after the order of Melchisedec, and not be called after the order of Aaron?
12 For the priesthood being changed, there is made of necessity a change also of the law.
13 For he of whom these things are spoken pertaineth to another tribe, of which no man gave attendance at the altar.
14 For it is evident that our Lord sprang out of Juda; of which tribe Moses spake nothing concerning priesthood.
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.
18 For there is verily a disannulling of the commandment going before for the weakness and unprofitableness thereof.
19 For the law made nothing perfect, but the bringing in of a better hope did; by the which we draw nigh unto God.
20 And inasmuch as not without an oath he was made priest:
21 (For those priests were made without an oath; but this with an oath by him that said unto him, The Lord sware and will not repent, Thou are a priest for ever after the order of Melchisedec;)
22 By so much was Jesus made a surety of a better testament.
23 And they truly were many priests, because they were not suffered to continue by reason of death:
24 But this man, because he continueth ever, hath an unchangeable priesthood.
25 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.
26 For such an high priest became us, who is holy, harmless, undefiled, separate from sinners, and made higher than the heavens;
27 Who needeth not daily, as those high priests, to offer up sacrifice, first for his own sins, and then for the people's: for this he did once, when he offered up himself.
28 For the law maketh men high priests which have infirmity; but the word of the oath, which was since the law, maketh the Son, who is consecrated for evermore."

It is clear from the above scripture that the mystical priesthood of Melchisedec (or Melchizedek) is the priesthood that God intended for His people from the very beginning, through the patriarchal covenants and ultimately in Christ's eternal covenant, which includes the matriarchal covenant of the Church -- The Bride of Christ!  This was Moses' cry in Numbers 11:29,

 "... would God that all the Lord's people were prophets, and that the Lord would put his spirit upon them"

 and of St. John the Revelator in Revelation 1:6,

 "And hath made us kings and priests unto God and his Father; to him be glory and dominion for ever and ever. Amen."

It was also one of the collective mystical visions of the prophets,

 "But in the days of the voice of the 7th angel, when he shall begin to sound, the mystery of God should be finished, as he hath declared to his servants the prophets."   Revelation 10:7

Ultimately we are saved, fulfilled, blessed and released by a Mystical Theology. We enter into the mystical reality that is God by the precious shed blood of Christ. Evangelicalism falls short by turning Christianity into an intellectual head trip, "He who knows the Bible the most, knows God the most." Charismatics belabor experiences that keep Christianity in the throes of spiritual immaturity. Orthodox Christians (e.g. Catholics) get lost in the 'churchianity' of rituals and traditions, etc. etc. But in these last days the Spirit of Jesus is bringing all things together; we are arriving at the land of spiritual maturity and fulfillment. In the inspired words of the apostle Peter, "But the God of all grace, who has called us unto his eternal glory by Christ Jesus, after that you have suffered a while, make you perfect, establish, strengthen, settle you." 1 Peter 5:10.  Finally, we Christians enjoy the fruit of those who have labored in the Spirit before us which culminates in Christ Jesus' perfect and eternal offering -- Himself incarnate, offered, suffered and glorified before the whole of the universe.

Who is Melchizedek? You and I dear fellow Christian.

As Jesus  the first Priest after the order of Melchizdek  proclaimed in St. John 8:58,   "Before Abraham was, I AM";  we Christians make the same proclamation. Hallelujah to JESUS!.