What does Teiresias (the prophet in the Land of the Dead) warn Odysseus against in his prophecy?

In The Odyssey Odysseus is warned by the blind prophet Tiresias that all of the sacred cattle of the Sun God Helios should be left alone. Tiresias says that the cattle should be avoided at whatever cost, and that if they are not, the men will all meet their doom.

He also tells Odysseus that when he returns home he will find suitors eating his food and courting his wife. He is told that he must send these men away or kill them. 

Lastly, he was told that he should find a place so far inland that the inhabitants ate unsalted meat and wouldn't know of the sea or be able to recognize an oar. Specifically he said Odysseus should walk until someone asked him about his oar and called it a "winnowing fan" rather than an oar (because they didn't know what an oar was, presumably). In that spot Odysseus is to stick the oar in the ground and make a sacrifice to Poseidon so that he can continue on his journey home safely. 

Odysseus intends to follow all of the prophet's instructions. He leaves to pray and in his absence tells his men to leave the cattle untouched. Unfortunately, food runs scarce and his men get hungry. Since they are temporarily trapped on the island, the men decide to fill their stomachs the only way they can think of: by killing and eating the sacred cattle. Helios is furious about this transgression, and he convinces Zeus to punish the men. On the trip home the ship wrecks and only Odysseus, who did not eat the sacred cattle, survives.