See also,
Gen 14:17 And the king of Sodom went out to meet him after his return from the slaughter of Chedorlaomer, and of the kings that were with him, at the valley of Shaveh, which is the king's dale.
Gen 14:18 And Melchizedek king of Salem brought forth bread and wine: and he was the priest of the most high God.
Gen 14:19 And he blessed him, and said, Blessed be Abram of the most high God, possessor of heaven and earth:
Gen 14:20 And blessed be the most high God, which hath delivered thine enemies into thy hand. And he gave him tithes of all.

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Melchizadek has a lot to do with the "New Covenant".
Probably the most mysterious character in the Bible.
The "New Covenant" (the covenant based upon Faith, Not works) is actually older than the "Old Covenant" (the covenant based upon works), and therefore takes precedent.
The tithe represents that which returns to God.
In the "Old Covenant", it is monetary.
It is My Opinion, that under the New Covenant it represents Believers, and the whole of Creation.
All of Creation = 10 representing the 10 Sephirah or stages of Creation.
The "/ " representing an abyss or "Firmament between the Permanent planes (or Heavenly realms) and the Temporary planes (or earthly realms).
This veil or abyss is represented by the Veil in the Temple that was rent "From top to bottom" at the crucifiction. (From top to bottom in my opinion means that it was God's doing.)
The 1 obviously represents God (who is One).
Under the "Old Covenant Law" No one could go through this veil Except the "high priest" once a year at "Atonement". To make an atonement for the people. This high priest was of the tribe of Levi.
Tithes were collected by priests. All of the tribe of Levi.
But Levi paid tithes "in Abraham" to Melchizadek. Levi was not born yet. He was inside of Abraham because he was a descendant of Abraham.
Believers are the beneficiaries of the "New Covenant" ...We are of the "Seed of Abraham" (Which is Christ) and the "New Covenant" which is actually the "Old Old Covenant". It was promised to Abraham "and to his Seed"
"Righteousness by Faith". "Abraham believed and it was counted to him as righteousness". Which seed We are.

Jesus is the High Priest "..forever after the order of Melchizadek".