In The Odyssey, what had Odysseus received from Maron at Ismarus? What laws of behavior and attitude does Polyphemus violate?
Among other gifts, Odysseus had received some "ruddy, irresistible wine" from Maron, "a priest of Apollo," because Odysseus "rescued him, his wife and children, reverent as [Odysseus and his crew] were [...]." In other words, in their siege on Ismarus or in the battle which followed the next morning, they saved Maron out of respect for the office the man performs for the gods. Because he is a priest of Apollo, and because Odysseus and his men revere the gods, they save Maron's life and family and leave them in peace. Odysseus tells King Alcinous of Phaeacia, that "Whenever [Maron's guests would] drink the deep-red mellow vintage, twenty cups of water he’d stir in one of wine." Wine then was much thicker and very much more potent than wine is now; it was customary to dilute the wine with water to make it an appropriate drink. Odysseus takes a skin of this very strong wine, undiluted, into the Cyclops' cave, and it is this undiluted and excellent wine with which he gets Polyphemus drunk.
When Polyphemus eats Odysseus's men instead of welcoming them and treating them with hospitality, he disobeys the religious imperative to offer what the Greeks called "xenia". Xenia referred to the reciprocal relationship between host and guest: the host must offer whatever he can to welcome a guest—even including giving him a gift—and the guest must not take advantage of the host's generosity, and because Zeus protected travelers, offering xenia was not really optional if one wanted to stay on Zeus's good side. Polyphemus says to Odysseus, "'We Cyclops never blink at Zeus and Zeus’s shield of storm and thunder, or any other blessed god—we’ve got more force by far. I’d never spare you in fear of Zeus’s hatred, you or your comrades here, unless I had the urge.'" In other words, then, Polyphemus brags that he is stronger than Zeus and so he does not have to obey Zeus's laws. This does not go well for him.
When Odysseus and his men sacked Ismarus, they spared Maron and his family (out of respect) and Maron then gave them gifts in return. He gave them "seven talents of fine gold, and a bowl of silver, with twelve jars of sweet wine, unblended."
This wine is so strong that it must be mixed with 20 parts of water to one part of wine. As Odysseus walks to the cave of Polyphemus, he carries with him the "goatskin of sweet black wine" in case he faces "some savage who would be of great strength, and would respect neither right nor law."
Polyphemus does not follow the Hospitality Rule that says strangers and beggars should be given food/drink/clothing if needed before they are asked who they are and why they are there. (This rule is important because the stranger could be a god.) Polyphemus instead eats Odysseus' men. He doesn't care about the law because his father is Poseidon. He feels that he can do whatever he wants and get away with it. He is huge and strong and thinks he is more powerful than the gods, so he doesn't follow the rules. This is where the powerful wine comes in handy. Odysseus offers it up to him, calling it the "wine of the gods" and Polyphemus passes out (drunk). This is when they blind him and are able to escape.