Jamieson, Fausset and Brown on Genesis 14:18

18. Melchizedek--This victory conferred a public benefit on that part of the country; and Abram, on his return, was treated with high respect and consideration, particularly by the king of Sodom and Melchizedek, who seems to have been one of the few native princes, if not the only one, who knew and worshipped, "the most high God," whom Abram served. This king who was a type of the Saviour (He 7:1), came to bless God for the victory which had been won, and in the name of God to bless Abram, by whose arms it had been achieved--a pious acknowledgment which we should imitate on succeeding in any lawful enterprise.