Most readers would struggle with today’s text from Hebrews 5:5-10. Martin Luther attempted to remove the book of Hebrews (and some others) altogether!
It uses ancient Hebrew concepts, symbols and metaphors to explain the role of Christ in brokering access to G-d. If you can work through that – you come to the clincher – that, after all, Christ was “designated by God a high priest according to the order of Melchizedek.”
Who was Melchizedek? There is scant reference to him in the Hebrew scriptures. Genesis 14:18-20 introduces him as the king of Salem who offers Abram hospitality and a blessing on Abram’s epic journey. Psalm 110:4 references him in glowing terms as G-d’s high priest. That’s all we have!
So what does the tradition say? Rabbinic literature and midrash is complex, but points to natural priestly or “go-between” attributes of Melchizedek upon which the latter Hebrew priesthood is modelled. Christian tradition points to Melchizedek as an ancient archetype of the Christ.
If one’s personal history is deeply steeped in the stories that create one’s identity, this would mean a great deal. Who is the Melchizedek in our life story that offers a pathway to understanding the role of Christ in our midst?
Wondering Pilgrim 
Nice take on the conundrum.
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