Route 66 is the main road of exodus for those fleeing from the harsh economic and environmental conditions of the Dust Bowl, stretching from the Mississippi to Bakersfield, California. Chapter 12 is a generalized vision of the harrowing journey west made by the displaced families. Thousands of people travel the highway, in constant fear over the state of their vehicles and their dwindling finances. Many are discouraged or run out of money. Their abandoned cars litter the highway. Yet, still more gather faith and strength from their fellow migrants and cling tenaciously to a narrow hope for a brighter future.
This chapter provides a preview of the Joads' journey to California. Many elements that will be specified in the next narrative chapter are highlighted here. The constant plea for water foreshadows the water that will be forgotten by the family, and the blown tire (and subsequent search for a replacement) is indicative of the mechanical difficulties that the family will face. Even the warnings about going to California will eventually be addressed in the narrative. The positive ending of the chapter likewise anticipates more specific treatment. Just as a broken-down family is rescued and whisked to California by a generic benefactor, so the Joads lend a hand to the Wilsons. After fixing their car, the two families will also travel together in order to ease difficulties of the journey.
Steinbeck's prose style is influenced strongly by the King James Bible, and one of the strongest examples of this influence is in the narrative structure of his plot. The Grapes of Wrath can be divided into three specific sections: the drought and preparation to leave the farm, the journey to California, and the arrival in California. The juxtaposition of two chapters of general observation marks the respective end and beginning of these first two sections. Each of these sections can be paralleled with the experiences of the Israelites in the Old Testament. They correspond respectively with the oppression of the Israelites by the Egyptians, their exodus out of Egypt, and their eventual entrance into the land of Canaan. Steinbeck's description in this chapter of the Okies as "a people in flight" alludes specifically to this biblical story, while his listing of the towns on Route 66 recalls scriptural listings of genealogical lineages.