Amid the haste of the Exodus — six hundred thousand men, a mixed multitude, unleavened bread, no time to wait — Moses stops to take the bones of Joseph.
Joseph had died in Egypt four hundred years before. Before his death he made the children of Israel swear: God will surely visit you. When that day comes, carry my bones up from here with you. He did not ask to be buried in Canaan immediately — he asked to be taken with the people when the time came.
The oath held through centuries of slavery. Moses, who had spoken with God at the burning bush, who had stood before Pharaoh ten times, who had watched the plagues unfold — takes a moment in the chaos of departure to fulfill a promise made by a dying man four generations before.
Joseph's bones travel through the Exodus, through the wilderness, through forty years of wandering, and are finally buried at Shechem in the parcel of ground that Jacob had bought. The longest journey of the Exodus was the one made by the bones of the man who had made it all possible.