In the series “12 reasons why Melchizedek was actually the pre-incarnate Word of God” the following article is reason # 2.
Melchizedek is the King of Salem which is to say the King of Peace.
To whom also Abraham gave a tenth part of all; first being by interpretation King of righteousness, and after that also King of Salem, which is, King of peace;
Genesis 14 gives a historical account of a conflict involving the patriarch Abraham and two groups of warring kings. There is another mysterious king mentioned in this same encounter who is not part of either group of warring kings. Genesis 14:18 refers to this mysterious king of Salem as Melchizedek (Genesis 14:18). He is thus far unaccounted for, yet he suddenly and briefly appears in the narrative, and were he not described as “the priest of the Most High God” in Genesis 14:18, it would seem completely acceptable (i.e. based upon Genesis 14 alone) to assume that Salem was just another territory that was in the proximity of the other ones listed in Genesis 14:1-2. However, three observations make this assumption highly problematic. The first is the fact that Melchizedek’s job as the priest of YAHWEH indicates that he was a heavenly and not an earthly priest (Hebrews 8:4).
The second is the fact that there is no biblical record of such a named territory contemporaneous to those of Genesis 14:1-2.
The third and perhaps most devastating obstacle of all is that Hebrews 7:2 completely repudiates the idea that the word Salem was ever meant to describe a territory, thus effectively disposing of any conversation concerning an earthly Melchizedek-ruled city named Salem.
Apart from Genesis 14:18, the word “Salem” is only ever used one other time in the Old Testament (Psalm 76:2) and there it poetically refers to the Millennial (or forthcoming) Jerusalem. Speaking on the identity of Salem, Dr. Henry Morris states:
This [i.e. Psalm 76:2] is the only place in the Old Testament where the name of “Jerusalem” (“the City of Peace”) is abbreviated to “Salem” (or simply “Peace”). Since this psalm is looking forward to the millennium, when God “shall speak peace” (Zec 9:10) to all nations, and “out of Zion shall go forth the law, and the word of the Lord from Jerusalem” (Isa 2:3), the city may then be known simply as Salem. It is true that Melchizedek was called “the king of Salem” in the days of Abraham (Gen 14:18), but this was probably a theophany, not referring to an earthly city at all, but to the heavenly city…A number of modern archaeologists have speculated that the name Salem was actually “Salim,” a god of the Amorites, but this idea is entirely hypothetical and is explicitly contradicted by this verse [i.e. Hebrews 7:2]. Similarly, it is commonly assumed that Salem was the original name of Jerusalem, but there is no other record of such a city at this time, either in archaeology or Scripture.
So again according to the Holy Spirit in Hebrews 7:2, the Salem of Genesis 14:18 was not a location but a title, namely, King of peace. Yet, some commentaries err on the side of blasphemy by calling Melchizedek a “Canaanite priest” or a “Canaanite king” living in an old “Canaanite city then called Salem” without any scriptural backing for such a position. Others (presumably due to Psalm 76:4) argue that Melchizedek was king of Jerusalem. For example:
[Melchizedek] bursts upon us as a priest-king, king of Salem, or Jerusalem, which we now know from discoveries in Egyptian records existed even in those very early ages 
When Abraham was returning from victory over a group of invaders, he was met by Melchizedek, the ruler of the Canaanite city-state of Salem. (This appears to be the place later known as Jerusalem.) 
One pattern that is easily discerned from the preponderance of Melchizedek-disparaging commentaries is their reliance upon incidental conjectures that proceed from various archaeological findings of questionable exegetical significance. One such finding is the 1887 discovery of the Tel el Armarna tablets (more than 350 clay tablets from the Royal Egyptian archives which purport an age within the 1400-1360 B.C. timeframe). Several commentators have appealed to excerpts from these tablets in an attempt to neuter or explain away some of Hebrews 7’s startling claims. For instance, some commentators have used the tablet’s writings to legitimize the idea that the term “Urusalim” from the text of one of these tablets is the Salem or Jerusalem from which Melchizedek supposedly reigned.
In an article on Melchizedek from the International Standard Bible Encyclopedia, David Francis Roberts asks:
Where did the author [of Hebrews] get the material for this description of Melchizedek? … The answer is perhaps to be had among the Tell el-Amarna Letters, among which are at least 6, probably 8, letters from a king of Urusalim to Amenophis IV, king of Egypt, whose “slave” the former calls himself. Urusalim is to be identified with Jerusalem, and the letters belong to circa 1400 BC. The name of this king is given as Abd-Khiba (or Abd-h̬iba), though Hommel, quoted by G.A. Smith, Jerusalem, II, 14, note 7, reads Chiba. Zimmer, in ZA, 1891, 246, says that it can be read Abditaba, and so Sayce (HDB, III, 335b) calls him ‛Ebhedh tōbh. The king tells his Egyptian overlord, “Neither my father nor my mother set me in this place: the mighty arm of the king (or, according to Sayce, “the arm of the mighty king”) established me in my father’s house” … The conclusions we come to are … The Epistle to the Hebrews makes use of … oral tradition which was not found in the Old Testament. It is this unwritten tradition that is possibly explained by the Tell el-Amarna Letters.
[David Francis Roberts, “Melchizedek,” in International Standard Bible Encyclopedia, ed. James Orr (Grand Rapids, Michigan: Wm. B. Eerdmans Publishing Co., c1915, 1939), in The Sword Project, v. 1.5.11 [CD-ROM] (Temple, AZ: CrossWire Bible Society, 1990-2008).]
That Roberts must ask where the Author of Hebrews got His description of Melchizedek betrays the realization that Roberts does not consider the Bible’s writings to be divine. For how could someone adhering to the idea of the divine authorship of Scripture begin to put forth such a baffling question? If Roberts really believed 2 Timothy 3:16’s proclamation that all Scripture is breathed out by God, then how could he ask where God got His “material for this description of Melchizedek”?
That the Author of Hebrews 7 is able to provide more information about Melchizedek than the Author of Genesis 14 is not even worthy of notice since, in the Bible, this type of progressive (i.e. accumulative) revelation happens all the time. For example, regarding the phenomenon of accumulative revelation in Hosea 12:4, Albert Barnes remarks:
He wept and made supplication unto Him – Jacob’s weeping is not mentioned by Moses [in Genesis 32:24-30]. Hosea then knew more than Moses related. He could not have gathered it out of Moses, for Moses relates the words of earnest supplication; yet the tone is that of one, by force of earnest energy, wresting, as it were, the blessing from God, not of one weeping. Yet Hosea adds this, in harmony with Moses.
[Hosea 12:4, Albert Barnes’ Notes on the Bible. A. Barnes (1798-1870).]
Based upon the rationale used by many unscrupulous Bible commentators such as Roberts, one would be forced to conclude that Hosea inferred fanciful details about Jacob’s encounter with the angel from tradition or extrabiblical writing instead of from the omniscient mind of the Holy Spirit. To deny that Hebrews 7 is providing additional, divine and previously unknown insight is to deny one of Christianity’s indispensable axioms. The implications of such a stance help us to see that the view about Melchizedek being an earthly king of Salem is a view that is ultimately birthed from a spirit of unbelief.
For the student of Scripture, the idea that the historical city which became known as Jerusalem is the same city of Salem that Melchizedek allegedly ruled, is unacceptable for several reasons. First of all, Ezekiel 16:3-4 makes Jerusalem a pagan entity at its birth; how could the “King of righteousness” preside over a province that would reek of unrighteousness for over 1000 years? 
Dr. Morris in his Defender’s Study Bible argues that Jerusalem was anti-God from her very beginnings and could never have therefore been Salem by adding:
That Melchizedek’s Salem could never have been Jerusalem is evident especially from Ezekiel 16:2-4 [where Jerusalem is said to have been born of an Amorite and a Hittite]. God’s description of the birth and early growth of the city of Jerusalem, using the symbol of a woman for the city, makes it clear that her history was completely pagan until God Himself made it His “holy city” under David and Solomon. This fact seems to eliminate the possibility that Jerusalem was originally Salem, the “city of peace,” ruled by Melchizedek
Yet, Dr. Arnold Fruchtenbaum’s Ariel Ministries furthers the dissemblance by saying:
Melchizedek was a type of Messiah but he was not a pre-incarnate Christ since every priest had to be human (Hebrews 5:1) and the Son was not human until the incarnation. Moreover, theophanies made their appearance and then disappeared after fulfilling their mission. They did not hold earthly offices such as king and priest of Jerusalem, which is what Melchizedek was. It is best just to see Melchizedek as a type of Messiah and leave it there.
Ariel Ministries’ argument is bad for many reasons. In spite of what the Ariel Ministries’ citation would have us believe, Hebrews 5:1 does not say that every priest has to be human. Hebrews 5:1 says:
“For every high priest taken from among men is ordained for men in things pertaining to God, that he may offer both gifts and sacrifices for sins.“
So we see that Hebrews 5:1 is not putting forth qualifications that must befall all high priests; rather, it is describing traits that befall high priests who are taken from among men. Obviously, Jesus, the Lamb of God Who was slain before the foundation of the world (Revelation 13:8) is perpetually a high priest (Hebrews 7:24) and yet so is Melchizedek (Hebrews 7:3) so we know from this fact alone that Melchizedek and Christ must be the same person. It is also instructive to realize that the Bible doesn’t provide rules or restrictions that must apply to theophanies, so to appeal to such a contrived rule is to, at best, erroneously argue from silence. Moreover, to claim that Melchizedek held “earthly offices such as king and priest of Jerusalem” is to conclude that Melchizedek, the “King of righteousness” whose priesthood is supposed to bring about perfection, was actually the mediator of failure and unrighteousness. After all, apart from Abraham and his household (Genesis 18:19), none of the inhabitants of Canaan (prior to Israel) were recipients of the righteousness which is by faith.
Bible commentators Easton and M’clintock also add to this confusion when they argue:
Melchizedek was a Canaanitish prince, a worshipper of the true God, and in his peculiar history and character an instructive type of our Lord, the great High Priest 
The best founded opinion seems to be that …[Melchizedek] was a principal person among the Canaanites and posterity of Noah, and eminent for holiness and justice, and therefore discharged the priestly as well as regal functions among the people…The way in which he is mentioned in Genesis would lead to the immediate inference that Melchizedek was of one blood with the children of Ham, among whom he lived, chief (like the king of Sodom) of a settled Canaanitish tribe. 
Bible commentator Bob Utley also adds to the confusion when he states:
[Melchizedek] was a Gentile king/priest of the old Canaanite city then called Salem, which later became Jebus and then later Jerusalem…The city may have gotten its name from the Hebrew term shalom which means “peace.” … The city is called Salem in Genesis 14, but Psalms 76:2 relates it to Jerusalem (i.e., Zion), which was called Jebus during the Canaanite period. 
A Gentile king? But Jesus says in John 8:6 that only the Jews know Who they worship because salvation is of the Jews. How could Melchizedek the immortal high priest of the Most High God be in league with the Gentiles before God officially appears to the Jews? Speaking to the Jews, Paul in Acts 13:46 confirms that the Word of God should first have been spoken to the Jews before the Gentiles. Why then would the high priest of the Most High God be caught ministering unto Gentiles at this time? Isn’t Abraham said to be the father of those who would be saved by faith (Romans 4:11-12, Luke 19:9)? In fact, according to Galatians 3:8, the reason why He (i.e. the Scriptures) preached the Gospel unto Abraham was because He foresaw that God would justify the heathen through faith. Hence, that Abraham is called the father of all who would be justified by faith and is yet unaffiliated with Melchizedek’s Salem or priesthood seems unexplainable. And isn’t it true that recipients of the atonement afforded by the Melchizedek priesthood must come to God by faith (Hebrews 7:25)?
If all of this is so, then what other people could Melchizedek have been ministering to at this time besides Abraham? Paul says in Romans 11:30: “For as ye in times past have not believed God, yet have now obtained mercy through their unbelief.” Therefore, the Bible makes it clear that God went to the Jews first then to the Gentiles. So it would seem that Romans 11:30 rules out any possible involvement of Melchizedek—Who’s priesthood brings about perfection (Hebrews 7:11, Hebrews 10:1-4)—with any gentile or pagan nations of that day. Besides, if this priesthood that brings about the perfection of its subjects was in practice in the supposed city of Salem, then where are those perfected citizens of Salem and why does God afterward introduce an inferior priesthood that can perfect no one (Hebrews 7:11)? Hebrews 7:19 tells us that the bringing in of a better hope (i.e. the Melchizedek Priesthood) brought about perfection but why does God bring in something better if that better thing had already preceded what is being replaced?
Theologian Matthew Henry, whose conception of Melchizedek is not without flaws, nevertheless, raises an important point when he states:
The most commonly received opinion is that Melchizedek was a Canaanitish prince, that reigned in Salem, and kept up the true religion there; but, if so, why his name should occur here only in all the story of Abram, and why Abram should have altars of his own and not attend the altars of his neighbor Melchizedek who was greater than he, seem unaccountable. 
Moreover, why would Melchizedek be king over a city that was later ruled and defiled by other pagan kings? If Salem is Jerusalem then you have a thousand years of pagan nations (culminating with the Jebusites) ruling over Melchizedek’s kingdom.  The Bible tells us that after defeating the Jebusites, king David made Jerusalem the capital city of Judah and of all Israel. For this reason, in certain passages of Scripture, Jerusalem is called the city of David (e.g. 2 Samuel 5:7; 1 Chronicles 11:5). But why isn’t Jerusalem instead called the city of Melchizedek? After all, according to the “commonly received opinion,” both Melchizedek and David ruled over Jerusalem. Melchizedek, in light of his inimitable titles (e.g. King of Righteousness, King of Peace, etc), must certainly be deemed a greater king than David! After all, unlike Melchizedek, David does not currently reside in Heaven from which place He receives tithes (Hebrews 7:8). Therefore, if Melchizedek was king of Jerusalem in the time contemporaneous to Abraham then shouldn’t we also expect the Scriptures to proclaim that Christ would sit on Melchizedek’s throne instead of David’s? After all, doesn’t truth concede that Melchizedek was a much greater king of Jerusalem than David? Yet, Melchizedek’s kingdom of Salem is apparently so insignificant that the Scriptures do not think to provide any details about this supposed kingdom but instead chooses to undermine it by explaining it away as a title (Hebrews 7:2).
Even, if one was to stipulate that Salem was, in fact, Jerusalem, i.e., a Jerusalem that existed during the time of Melchizedek, why should it be some contrived pagan entity and not the “heavenly Jerusalem” which Hebrews 12:22 calls “mount Sion…the city of the living God…and…an innumerable company of angels”? After all, doesn’t Genesis 14:18 call Melchizedek “the priest of the most high God”? And doesn’t Hebrews 8:1-2 implicitly bestow this same title upon Christ? Because of this very title, Hebrews 8:4 reminds us that neither Christ nor Melchizedek could have been an earthly high priest.
Therefore, yet to be answered is the question of how a godly, immortal priest who sponsored a priesthood that brings about perfection could be confused with the likes of a Canaanite king? Agreeing with this analysis, Dr. Henry Morris’ Defender’s Study Bible also questions “how such a godly king and priest as Melchizedek could be ruling a city in such an ungodly land as Canaan and, why, if he did, Abram would have had no other contact with him.” The solution according to the same commentary is that “it seems better to take the words [of Hebrews 7:2] literally, in which case they could only be applicable to Christ Himself, appearing here [i.e. in Genesis 14:28] to Abram in a theophany.”
In conclusion, it is clear that Salem was not a city at all but was instead a title owned by the Second Person of the Trinity who appeared to Abram in a theophany. The Second Person of the triune God, namely, Yeshua (a.k.a Jesus) the Messiah is both the Son of God and the Word of God. That He is here (i.e. in Hebrews 7:2) called the “King of Peace” aptly coincides with verses such as Isaiah 9:6-7 (Prince of Peace) and 2 Thessalonians 3:16 (Lord of Peace), where He is likewise acknowledged to be the exclusive Proprietor of Peace. To assign such a title to any other person (as the aforementioned Bible commentators have done) is not only sacrilegious but betrays the willingness of these authors to embrace unscriptural and irrational conclusions on the slightest of archaeological conjecture. In light of what the Author of Hebrews has to say about Melchizedek, to yet proceed with the understanding that he was some earthly king whose priesthood apparently mediated decades of failure demonstrates a profound misunderstanding of the whole counsel of God.
1. Genesis 14:18, The Defender’s Study Bible, Henry M. Morris, Ph.D., LL.D., Litt.D.
5. Psalms 76:2 & Hebrews 7:2, The Defender’s Study Bible, Henry M. Morris, Ph.D., LL.D., Litt.D.
6. See notes on Hebrews 7:1-3, The People’s New Testament (1891), B. W. Johnson
7. See notes on Melchizedek, Bridgeway Bible Dictionary, Don Fleming
8. http://www.ariel.org/qa/qmelchiz.htm, Ariel Ministries, Dr. Arnold Fructenbaum
9. See topic Melchizedek, Illustrated Bible Dictionary, M.G. Easton M.A., D.D.
10. See notes on Melchizedek, Cyclopedia Of Biblical, Theological And Ecclesiastical Literature, Rev John M’clintock, D.D., James Strong, S.T.D.
11. See notes on Hebrews 7:1-3, Bible Lessons International, Dr. Bob Utley
12. See notes on Genesis 14:17-20, Matthew Henry’s Commentary on the Whole Bible, Dr. Matthew Henry
13. [The meeting between Abraham and Melchizedek] was c.1000 years prior to David’s conquest of the city (2 Sam 5:6-10). See Hebrews 7, E. Melchizedek Like The Son Of God (7:1-3), The College Press NIV Commentary New Testament, David A. Fiensy, Ph.D., Jack Cottrell, Ph.D., Tony Ash, Ph.D.
14. See notes on Ezekiel 16:4, The Defender’s Study Bible, Henry M. Morris, Ph.D., LL.D., Litt.D.