How is the King of Salem related to and contribute to or detract from Santiago's journey's success in The Alchemist by Coelho?

Melchizedek, also known as the King of Salem,

contributes to Santiago's journey in by teaching the boy to learn
about
himself, to find the right path and to learn to be wise. The King of
Salem helps Santiago
understand that what people most want is to learn their
personal Legends, the idea about
themselves that is most true and to which
they must stay attuned and committed. He also
contributes to Santiago's
journey by giving hints and clues as to where to find his treasure. In

addition, he teaches Santiago to be wise by making a deal with him to trade one-tenth of
his
sheep for Malchizedek's clue to the treasure.