Genesis 14:18
16 He retrieved all the stolen property. He also brought back his nephew Lot and his possessions, as well as the women and the rest of the people. 17 After Abram returned from defeating Kedorlaomer and the kings who were with him, the king of Sodom went out to meet Abram in the Valley of Shaveh (known as the King’s Valley). 18 Melchizedek king of Salem brought out bread and wine. (Now he was the priest of the Most High God.) 19 He blessed Abram, saying, “Blessed be Abram by the Most High God, Creator of heaven and earth. 20 Worthy of praise is the Most High God, who delivered your enemies into your hand.” Abram gave Melchizedek a tenth of everything.
Josephus Antiquities of the Jews 1.10.2
2 So Abram, when he had saved the captive Sodomites, who had been taken by the Assyrians, and Lot also, his kinsman, returned home in peace. Now the King of Sodom met him at a certain place, which they called The King’s dale, where Melchisedeck, King of the city Salem, received him. That name signifies, The righteous King: and such he was without dispute; insomuch that, on this account, he was made the Priest of God. However, they afterward called Salem Jerusalem. Now this Melchisedec supplied Abram’s army in an hospitable manner, and gave them provisions in abundance: and as they were feasting, he began to praise him, and to bless God for subduing his enemies under him. And when Abram gave him the tenth part of his prey, he accepted of the gift. But the King of Sodom desired Abram to take the prey; but intreated that he might have those men restored to him whom Abram had saved from the Assyrians, because they belonged to him. But Abram would not do so; nor would make any other advantage of that prey, than what his servants had eaten: but still insisted that he should afford a part to his friends that had assisted him in the battel. The first of them was called Eschol, and then Enner, and Mambre.
Notes and References
"... Melchizedek is a priest: although Targum Pseudo-Jonathan does not use the word khn here, Shem is so styled in Targum Pseudo-Jonathan Genesis 38:6, 24. Furthermore, the expression ‘at that time he was ministering’ makes best sense if ‘ministering’, mšmš, is taken to mean ‘acting as priest’, since an ordered temporal succession of priests is attested elsewhere in rabbinic tradition. The title Shem the Great suggests a well-known worthy with a history to his credit: what this might be, we shall discover presently. Targum Pseudo-Jonathan uniquely calls him the righteous king, an interpretation of the name Melchizedek found also in Philo and Josephus. This meaning of the name was known also to the writer of Hebrews 7:2, as is Targum Pseudo-Jonathan’s note that he ‘went out to meet Abram’. None of these unique details in Targum Pseudo-Jonathan seems directed against Christianity. Rather, the Epistle to the Hebrews may here be dependent on Jewish tradition episodes from Genesis certainly pre-dates the Christian era, and is intent on presenting Abraham as a sacrificing priest ..."
Hayward, Robert Targums and the Transmission of Scripture into Judaism and Christianity (pp. 9-10) Brill, 2010