The Waste Land
How we cite our quotes:
What are the roots that clutch, what branches grow
Out of this stony rubbish? Son of man,
You cannot say, or guess, for you know only
A heap of broken images […] (19-22)
Since Eliot borrows from the book of Ezekiel in this passage, the speaker here might actually be God. Or at least it might as well be, because the person speaking asks you (yeah that's right—you) what hope you can possibly have for finding comfort in the "stony rubbish" of the modern world. People in the past had total faith in the Bible, and this faith allowed them to think that everything in their lives happened for a purpose. But you, the modern reader, "know only / A heap of broken images." In other words, you might know a few things here and there about religion, but you don't live it as a day-to-day reality. This passage brings up the image of a spiritual whole that's been shattered or broken into fragments by modernity, and in this sense, Eliot conveys the sense of spiritual uneasiness that dominates the modern world.
I will show you fear in a handful of dust. (30)
Pardon us while we pee our pants. Continuing with the heavily Biblical (and scary) tone, the speaker tells you that it's possible to experience fear in nothing more than a handful of dust. Now why would that be? Well because according to the Christian funeral service, every person starts out as dust, then returns to dust when they die. Christianity is really big on reminding us that, compared to the glory of God, all we are is dust in the wind. Here Eliot really wants to impress you with the fire and brimstone quality of religion, since he's really invested in reminding you that we're all going to croak someday. The logic here is that the more you think about your own mortality, the more you'll start seeking spiritual guidance.
By the waters of Leman I sat down and wept… (182)
Eliot alludes to the book of Psalms 137.1, which reads, "By the rivers of Babylon, there we sat down, yea, we wept, when we remembered Zion." In this case, Eliot practices what he preaches (no pun intended), and actually uses a situation from the Bible to communicate the exact emotion he's feeling. (Now that's an allusion.) His speaker feels like he's living in exile in the modern world, longing to get back to the "homeland" of his past. Similarly, the speakers of the cited Bible passage have been exiled from their homeland of Zion, and yearn to get back to it. Eliot in this case is suggesting that there is a feeling of spiritual homelessness in the modern world that can be helped by referring to a spiritual text like the Bible.