Psalm 137 is a powerful expression of longing and lament. The Israelites, exiled in Babylon by the Euphrates River, mourn their lost homeland, Jerusalem. They sing of their despair by the rivers, unable to forget Zion (Jerusalem). The psalm flips between deep sadness at the destruction of their holy city and a call for revenge against their captors, the Babylonians. The writer even curses himself if he forgets Jerusalem, showing the centrality of their homeland to their faith.