Argos, Odysseus' dog, is symbolic of the kingdom of Ithaca. When Odysseus left Ithaca, Argos was a strong and quick dog renowned for his tracking prowess; however, Argos, like the rest of his house and kingdom, had been neglected by the servants and suitors. As Homer writes in book 17:

Now that his master was gone he was lying neglected on the heaps of mule and cow dung that lay in front of the stable doors till the men should come and draw it away to manure the great close; and he was full of fleas.

When Odysseus returns to Ithaca--disguised as a beggar--Argos is the only one who recognizes his master.

As soon as he saw Odysseus standing there, he dropped his ears and wagged his tail, but he could not get close up to his master.

Odysseus--still in disguise--inquires about the dog, and Eumaeus replies that he used to be a noble hunting companion.

But now he has fallen on evil times, for his master is dead and gone, and the women take no care of him. Servants never do their work when their master's hand is no longer over them, for Zeus takes half the goodness out of a man when he makes a slave of him.

To Odysseus' private dismay, Argos dies. This heart-wrenching passage symbolizes the danger in which Ithaca and Odysseus' house lies. His family has waited for him for two decades (like Argos), but they cannot wait forever. The suitors are quite literally eating them out of house and home. Odysseus must hurry and put his plan into action to reclaim his place as king of Ithaca and husband of Penelope.