Thesis: The Bible, The Odyssey by Homer and a Christmas Story by Jean Shepard, all relate to The Alchemist by Paulo Coelho in the way that the main characters give up something for the better.
Detail: "'If you [Santiago] want to learn about your own treasure, you will have to give me [Melchizedek] one-tenth of your flock.'" (Coelho 27)
Commentary: Santiago had to give up one-tenth of his flock to fulfill his personal legend. Just like in the Bible in Hebrews 7:2 it states, "Then Abraham took a tenth of all he had captured in battle and gave it to Melchizedek. The name Melchizedek means 'king of justice,' and king of Salem means 'king of peace.'" Abraham had to give up a tenth of his belongings to Melchizedek just like Santiago gave up one-tenth of his sheep. Santiago did this so he could fulfill his personal legend as Abraham did this to repay Melchizedek for helping him conquer four kings.
Detail: "'I'm going away,' he [Santiago] said. 'And I want you to know that I'm coming back.'" (Coelho 126)
Commentary: Santiago had to leave Fatima to fulfill his personal legend just like in the Odyssey, Odysseus had to leave the one that he loved, Penelope, so that he could go off and fight in the Trojan war. Penelope stated once he returned, "I very well remember what you were when you went upon your long-oared ship away from Ithaca." (Homer 23.225). This was when Odysseus had returned from his long voyage. In both instances, Odysseus and Santiago had to leave someone they loved for the better. Santiago left Fatima to go seek treasure, while Odysseus left Penelope to fight in a war (which ended in him getting treasure).
Detail: "...it [the boys heart] told him something else that the boy had never noticed: it told the boy of dangers that had threatened him, but that he had never perceived . His heart said that one time it had hidden the rifle the boy had taken from his father, because of the possibility that the boy might wound himself." (Coelho 139)
Commentary: As I read this part my mind instantly took me to the Movie, A Christmas Story. In A Christmas Story, the boy gets a gun for Christmas, but his parents tell him to be careful and to not hurt himself or "shoot his eye out". Thus connecting to Santiago when his parents took the rifle away so he wouldn't hurt himself. He had to give up his rifle for the better.
Conclusion: All in all, The Bible, The Odyssey by Homer and a Christmas Story by Jean Shepard all show examples of how sometimes it's better to give up something, even though you love it, for the better. Whether it's giving up your own belongings, leaving someone you love or giving up a gun as a child because it's not safe.