Martin McNamara, «Melchizedek: Gen 14,17-20 in the Targums, in Rabbinic and Early Christian Literature», Vol. 81 (2000) 1-31

The essay is introduced by some words on the nature of the Aramaic translations of Gen 14 used in the study (the Tgs. Onq., Pal. Tgs. as in Tgs. Neof. I, Frg. Tgs., Ps.-J.). Tg. Neof. identifies the Valley of Shaveh (Gen 14,17) as the Valley of the Gardens (pardesaya). The value of Tg. Neof.’s evidence here is doubtful. Most Targums retain Melchizedek as a personal name (not so Tg. Ps.-J.). Salem of v. 18 is identified as Jerusalem. Melchizedek is identified as Shem, son of Noah, mainly because of the life-span assigned to Shem in Gen 11. The question of Melchizedek’s priesthood in early rabbinic tradition and in the Targums (Tg. Gen 14; Tg Ps. 110) is considered, as is also the use of Jewish targumic-type tradition on Melchizedek in such early Fathers as Jerome, Ephrem, and Theodore of Mopsuestia.

the frequent use of the phrase "high priesthood" in Tg. Neof. (and the Pal. Tgs) is regarded by some as an indication of late origin for these texts⁵⁵. The matter requires more detailed study before a firm conclusion can be reached. An argument favouring a later date for the designation in Tg. Neof. and the few texts of Frg. Tg. might be drawn from the Cairo Genizah text of Tg. Gen 40,13.15 in Klein’s MS E, parchment (considered "early", that is, 9^th–10^th to mid-11^th century), where the text is the same as Tg. Neof. but in both instances lacks the adjective "high"⁵⁶. MS Z, with the added term "high", in paper, is dated as "middle", that is mid-11^th to late 14^th century.

        Tg.Onq. Gen 14, 18 does not render the HT word "priest" at all. It translates: "Now Melchizedek, king of Jerusalem, brought out bread and wine, and he was ministering (#$ym#$m; mesammes, pael participle) before God Most High". It may be that Tg. Onq.’s translation is intentional, possibly occasioned by a view such as that of R. Ishmael. Elsewhere Tg. Onq. gives a careful rendering of the Hebrew word Nhk in keeping with the context. In Gen 41,45.50, 46,21 Putiphar, priest (Nhk) of On (of the MT) is called )br, "prince". The other pagan priests (HT: Mynhk) of Egypt are called )yrmk. In Exod 2,16; 3,1; 18,1 Jethro, the priest (Nhk) of Midian is translated as )br, "prince". In Exod 19,6 Mynhk is rendered in Tg. Onq. as )ynhk. In all references to Aaron the priest