Al Naharot Bavel

Psalms chapter 137 known as "Al Neharot Bavel" is commonly recited during the Nine Days - the period of mourning leading to Tisha B'Av. What are the main messages that lie within this chapter? By closely examining the words and imagery, we can learn about the danger in the comforts of exile, as well as the important role that the Land of Israel and, more specifically, Jerusalem, play in the poet's relationship with God.