A noiseless patient spider,
I mark'd where on a little promontory it stood isolated,
Mark'd how to explore the vacant vast surrounding,
It launch'd forth filament, filament, filament, out of itself,
Ever unreeling them, ever tirelessly speeding them.
And you O my soul where you stand,
Surrounded, detached, in measureless oceans of space,
Ceaselessly musing, venturing, throwing, seeking the spheres to connect them,
Till the bridge you will need be form'd, till the ductile anchor hold,
Till the gossamer thread you fling catch somewhere, O my soul.
This poem is about a man and his soul. After reading it a few times, I see that he is searching within himself in his soul for purpose, for a reason. He refers to his soul as a spider, patient and quite, waiting for a catch to come along. This "catch" would be the reason or purpose in his life. The man is alone in a vast surrounding of nothing as symbolized as the spider on the isolated promontory (a.k.a. a projecting piece of land), meaning his soul is in a lonesome, quiet state, waiting for something to come along patiently. The young man is fervently searching for this idea of a purpose (Line 8 "Ceaselessly musing, venturing, throwing, seeking the spheres to connect them...") until his "gossamer thread" (thin or flimsy outreach) connects with whatever his soul may need.