Answer:
Holism/Unity (Casy’s Philosophy)
As a fire-branding minister, Casy spread God’s word, but after his sermons he slept with women from his congregation who were excited by his preaching. Coming home from a trip to the wilderness (one of several attributes he shares with Christ), Casy crosses paths with Tom Joad. Casy confesses his sins yet denounces the organized Christianity he practiced in the past. Casy now believes that “‘maybe it’s all men an’ all women we love; maybe that’s the Holy Sperit—the human sperit—the whole shebang. Maybe all men got one big soul ever’body’s a part of’” (32-33). Later in the novel, when Casy delivers Grampa’s eulogy, he says, “‘He was alive, an’ that’s what matters. An’ now he’s dead, an’ that don’t matter. Heard a fella tell a poem one time, an’ he says “All that lives is holy.” Got to thinkin’, an’ purty soon it means more than the words says’” (196-97). Casy’s philosophy is thus constructed on the idea that all living beings are intrinsically linked, with love and compassion being major components of his belief. When Casy dies, Tom adopts his way of thinking, promising to take Casy’s leadership platform to the displaced migrants:
‘I’ll be ever’where—wherever you look. Wherever they’s a fight so hungry people can at, I’ll be there. Wherever they’s a cop beatin’ up a guy, I’ll be there. If Casy knowed, why, I’ll be in the way guys yell when they’re mad an’—I’ll be in the way kids laugh when they’re hungry an’ they know supper’s ready. An’ when our folks eat the stuff they raise an’ live in the houses they build—why, I’ll be there. See? God, I’m talkin’ like Casy.’ (419)
This speech marks Tom’s final appearance in the novel, turning him into a symbol of sacrifice as he carries on Casy’s mission of unifying the migrant workers. Tom offers a glimmer of hope in solving the novel’s—and, by extension, society’s—problems.
Explanation:
https://sits.sjsu.edu/curriculum-resources/the-grapes-of-wrath/major-themes/
Hope this helps.