I believe the significance of Chapter 24 is that it illustrates so clearly how the way to the peace and happiness Wang Lung longs for throughout his life is there all the time, right before his eyes, in the person of his wife, yet blinded as he is by his lust for beauty and riches, he overlooks her completely, until it is too late.
The Chapter opens with Wang Lung saying to himself "that peace (is) in his house", but it is clear from the onset that his household is in chaos. His spoiled son wants to go away to school, but Wang Lung refuses; in anger and frustration, his son finds amusement instead with his father's concubine, Lotus. In the meantime, his humble wife O-lan is obviously ill, but
"she rose at dawn and she did her work and Wang Lung saw her only as he saw the table or his chair or a tree in the court, never even so keenly as he might see one of the oxen drooping its head or a pig that would not eat".
O-lan slaves everyday keeping the household in order and meeting his every need, yet Wang Lungnever thinks of asking her if she would like him,
"with the silver (he has) to spare, to hire a servant or a slave...it did not occur to him that there was any need of this".
Like the good earth to which Wang Lung always returns when things get rough, O-lan is the earth mother, strong, steady, and sensible. It is ironic that Wang Lung overlooks her so completely, even when it is evident that his pursuit of superficial assets brings him no lasting satisfaction. The Chapter ends with the juxtaposition of two images - that of Wang Lung going out to the fields exhausted by the turmoil in his home, posed against the picture of
"O-lan sitting sewing on some garment of his, and when he passed she said nothing, and if she had heard the beating and the screaming, she made no sign of it" (Chapter 24).