Order of Melchizedek
Melchizedek, of the Most High God, is mention in Genesis 14:18 with Abraham, but is NOT mentioned again until Psalms 110:4. This psalm (song or poem) was written by King David. YHVH has taken an unrelenting (unrepenting) oath for an eternal priest who is also a King. There are fourteen generations between Abraham and King David, see Matthew 1:17. The explanation about Melchizedek and His priestly order is not revealed until Hebrews chapters 5, 6, and 7. The revelation and understanding of Melchizedek spans the entire Word.
Gen 14:18 – 20
Then Melchizedek king of Salem brought out bread and wine; he was the priest of God Most High.
And he blessed him and said: “Blessed be Abram of God Most High, Possessor of heaven and earth;
And blessed be God Most High, Who has delivered your enemies into your hand.” And he gave him a tithe of all.
Bereshit 14:18 – 20
And Malchizedek the king of Salem brought out bread and wine, and he was a priest to the Most High God.
And he blessed him, and he said, “Blessed be Abram to the Most High God, Who possesses heaven and earth.
And blessed be the Most High God, Who has delivered your adversaries into your hand,” and he gave him a tithe from all.
El Elyon - God Most High
New King James:
The LORD has sworn And will not relent, “You are a priest forever According to the order of Melchizedek.”
Tanach:
The Lord swore and will not repent; you are a priest forever because of the speech of Malchizedek.
So all the generations from Abraham to David are fourteen generations, from David until the captivity in Babylon are fourteen generations, and from the captivity in Babylon until the Christ are fourteen generations.
As He also says in another place:
“You are a priest forever According to the order of Melchizedek”;
called by God as High Priest “according to the order of Melchizedek,”
…where the forerunner has entered for us, even Jesus, having become High Priest forever according to the order of Melchizedek.
For such a High Priest was fitting for us, who is holy, harmless, undefiled, separate from sinners, and has become higher than the heavens; who does not need daily, as those high priests, to offer up sacrifices, first for His own sins and then for the people’s, for this He did once for all when He offered up Himself. For the law appoints as high priests men who have weakness, but the word of the oath, which came after the law, appoints the Son who has been perfected forever.