How we cite our quotes:
the wish of my heart urges all the time
my spirit to go forth, that I, far from here,
should seek the homeland of a foreign people— (36-38)
Talk about conflicted! The speaker feels his heart urge his spirit to set forth, and in doing so, actually divides himself in three. He's a body, a heart, and a spirit.
Not for him is the sound of the harp nor the giving of rings
nor pleasure in woman nor worldly glory—
nor anything at all unless the tossing of the waves;
but he always has a longing he who strives on the waves. (44-47)
The seafarer is consumed by a "longing." Could that explain his lack of pleasure in earthly things? It just might, if we knew what he was longing for. But of course, we're kept in the dark here.
And now my spirit twists out of my breast,
my spirit out in the waterways,
over the whale's path it soars widely
through all the corners of the world-- it comes back to me
eager and unsated; […] (58-62)
Our guy is literally torn into two pieces – his spirit and his body. Even travel all over the world fails to put an end to the seafarer's constant longing. The word "unsated," often used in relation to physical hunger, connects this longing to the hunger that "tears from within" in line 11.