The activity of John the Baptist continues to be a focus of lively, revisionary discussion. Some scholars have questioned the Synoptic accounts of the Jordan as a locale for mass purificatory rites on grounds of practicality, and have sought to identify places named in the Fourth Gospel with sites in Samaria and springs east of the Jordan as more suitable locations. Others have wondered whether the accounts of John's activity have any precedents at all in Jewish purificatory rites. This paper acknowledges difficulties in making the accounts of John's baptism in the Jordan fit the profile of traditional purificatory rites. At the same time it draws attention to problems in trying to assimilate John's baptism to such rites. A counter-proposal is offered which suggests that the key to understanding John's baptism lies in seeing the Jordan as the boundary and point of entry into the land promised by Yahweh to Israel. John was calling for a morally purified Israel that was fit to dwell in the holy land. In emulation of the original entry depicted in the Book of Joshua, John's baptism called on Israelites to exit the land, and return across the Jordan under the leadership of John in order to repossess the land as a consecrated people. The crossing of the Jordan holds the key to what John was doing.