The imagery of tears is the Poet's favorite way of depicting suffering. That, along with wailing and eating children.
Tears on Their Pillows
Seriously. We're not kidding. This book is quite the cry-me-a-river story:
[Zion] weeps bitterly in the night, with tears on her cheeks. (1:2)
For these things I weep; my eyes flow with tears. (1:16)
My eyes are spent with weeping. (2:11)
Let tears stream down like a torrent day and night! Give yourself no rest, your eyes no respite! (2:18)
My eyes flow with rivers of tears because of the destruction of my people. (3:48)
My eyes will flow without ceasing, without respite. (3:49)
So, what exactly is going on with all the waterworks? Well, Lamentations is a sad story. The Poet is in mourning over the destruction of Jerusalem and being forced into exile in Babylon. All these tears symbolize how uncontrollable and oppressive the people's sadness is. The misery is almost too much to bear. In fact, by the end of this whole thing, the Poet is all cried out. He's wept and wailed so much that he's totally spent. Now that's suffering.
Why does water leak out of our eyes when we get a little emotional? Unlike tears that wash away dirt or lubricate the eyes, tears of sadness don't do anything to help our bodies. The waterworks are just an outward sign of our inner misery. That's why some scientists think that humans might cry as a way to strengthen our bonds with other people and show the world how we're feeling.
Lamentations—bringing people together for weep fests since 587 BCE.