 After the failure of the initial assault, a meeting between the various leaders was organized in which it was agreed upon that a more concerted attack would be required in the future.On 17 June, a party of Genoese mariners under Guglielmo Embriaco arrived at Jaffa, and provided the Crusaders with skilled engineers, and perhaps more critically, supplies of timber (stripped from the ships) to build siege engines.The Crusaders' morale was raised when a priest, Peter Desiderius, claimed to have had a divine vision, of Bishop Adhemar, instructing them to fast and then march in a barefoot procession around the city walls, after which the city would fall, following the Biblical story of Joshua at the siege of Jericho.