"Now this Melchizedek was a king over the land of Salem; and his people had waxed strong in iniquity and abomination; yea, they had all gone astray; they were full of all manner of wickedness; But Melchizedek having exercised mighty faith, and received the office of the high priesthood according to the holy order of God, did preach repentance unto his people. And behold, they did repent; and Melchizedek did establish peace in the land in his days; therefore he was called the prince of peace, for he was the king of Salem; and he did reign under his father."
He was a king over people who had "waxed strong" in both "iniquity" and also "abomination." Keep in mind that "waxing strong" means to be increasingly determined or committed. "Iniquity" is generally evil practice, but "abomination" involves the religious justification of wrongdoing. That is, something becomes "abominable" when it is motivated out of a false form of religious observance or is justified because of religious error.
The people to whom Melchizedek would minister were not simply in error, they were motivated by a false set of religious beliefs and errors. The result was that "they had all gone astray." They were "full of all manner of wickedness." This was a challenging audience for this man to minister to and try to convert to the truth.
Melchizedek began by "exercising mighty faith" in order to understand the truth and discern the difference between truth and error. Remember how difficult it is to be taught truth. It is more difficult to learn truth than it is to perform miracles. (3 Ne. 17: 2-7.) Despite this, Melchizedek was able to set aside all he beheld and through faith acquire an understanding of the truth for himself. Conferred upon him as part of this education was the priestly authority with which to minister to others.
He "did preach repentance unto his people." This required him to expose the errors, show them they were involved in iniquity and to expose how their religious errors had made them abominable. This preaching is always most difficult because it confronts the audience with a challenge to their mistaken beliefs, and false religion. There is a risk of violence when this happens. People who entertain abominable religious practices are more often moved to violence than to repentance. The Lord was greeted with violence. So was Lehi, Isaiah, Nephi, Samuel the Lamanite, Abinadi, Peter, Paul, Stephen, James, Zacharias and too many others to mention. To their credit, and to Melchizedek's, the preaching resulted in repentance.
The serious errors, iniquity, and abominations of these people did not prevent Melchizedek from establishing a Zion. These people were able to acquire "peace in the land" because of their repentance. As used here, however, peace means more than the absence of violence, it means the presence of the Lord.
The statement that he established peace as the King of Salem (Shalom means peace) and "he did reign under his father" is a play on words. Which "father" is being identified in the statement. Was it Noah, or Gabriel? (A man who would also be translated and have a ministry as the Lord's herald before the birth of John the Baptist and Christ.) Or was the "father" Him would would declare that Melchizedek was "begotten" as a "son of God?" It likely meant both. But it is also likely written this way to let those who do not understand what is being said to read it in a way that conceals the dual meanings. The scriptures are filled with such dual meanings.
What is hopeful for us today, is that no matter how much "iniquity" and religious error we engage in that results in our "abominations" in our pride and foolishness, we still may be candidates to receive something similar to what befell the City of Salem. The first step is to acquire the presence of this priesthood through individual repentance.
We envy these ancients. But we do nothing to try and follow the pattern revealed to us in their course. The Book of Mormon is a course in ancient failure and ancient success. We just do not respect what we have in that volume.
Well, let us press on...