After the boy has sold his sheep, and has 6 sheep (10% payment) ready to give to the King of Salem, Melchizedek tells to the boy a parable, not a fable, to help him on his journey. The parable is about a boy who visits a wise man to find out the secret of happiness. Before the man will talk to him, the boy is charged to carry two drops of oil on a spoon while walking through the palace. When the boy comes back, he has the oil but does not know anything about the wise man's home. Given a second chance to learn about the wise man by observing his home, the boy returns without the oil, but had observed the house. Santiago believes that the moral of the story is as follows:
"The shepherd said nothing. He understood the story the old king had told him. A shepherd may like to travel, but he should never forget about his sheep" (32).
As Santiago travels to the Egyptian pyramids, he encounters some discouraging setbacks which make him think about going back to his sheep. He feels at times that the journey in search of his Personal Legend is too difficult, and he can always go back to what he knows as a shepherd if he fails. This can't be the moral of the story, though.
The wise man represents God and the palace represents the world that the boy must learn about in order to receive the wisdom he seeks. The oil on the spoon is a reminder to focus on the little details, or omens, while also wandering around and observing God's house (the world). For example, Santiago knows about following omens from his grandfather, and Melchizedek validates his feelings by telling him to learn how to read the omens in order to help him fulfill his Personal Legend. The boy in the palace, on the other hand, either focuses on the little things too much (the oil) and doesn't pay attention to the palace around him (the world); or he observes the palace, but forgets about the little details that would teach him what he needs to know in order to achieve his goal.
Therefore, Santiago understands the parable to mean that he can always go back to his sheep if he fails; but that's not the point of the story. The story teaches him to pay attention to both omens and the world; and as he travels the world, he should learn about God who will help him to find his treasure. The point of going on the journey is not to fail and go back to what he was doing before. The point of going to Egypt is for Santiago to fulfill his Personal Legend and find his treasure. Along the way, though, as portrayed in the parable, Santiago must pay attention to everything around him, big or small, in order to achieve his goals.