land—a time when Yahweh in his power brought his people out from exile and defeated a superpower in doing so. If Book 4 was gathered during the exile (when the people were held in exile by the superpower of their day), it is very easy to see why this psalm was chosen to initiate this collection. The fact that this is “a prayer of Moses” (emphasis added) would also be significant for the original readers of this collection because Moses’s prayers were deemed to be efficacious. For example, the Lord