The symbol in the excerpt <em>is the new cloak. </em>
Symbols in literature are used to signify ideas through them, which means that the author can use a symbol with the purpose of giving them symbolic meanings that in fact are completely different from the literal sense. For example, in our daily life, we can say that a white pigeon is a symbol of peace or that the color red is a symbol of love.
Since the excerpt is from the Odyssey, I can deduce that the new cloak represents Odysseus’s change from an exhausted traveler to the returning hero.