The "King of Salem" refers to a biblical figure named Melchizedek, who appears in the Book of Genesis. He is described as the king of Salem, which is often identified with the ancient city of Jerusalem. Melchizedek is notable for being both a king and a priest, blessing Abram (later known as Abraham) and receiving a tithe from him. In the New Testament, Melchizedek is mentioned in the Book of Hebrews, where he is used as a symbol of Christ's eternal priesthood. His unique dual role as king and priest highlights themes of divine authority and spiritual leadership, making him an important figure in both Judaism and Christianity.