The "image" of Rose of Sharon nursing a starving stranger in a barn is very similar to the one of Roman Charity. It might be interesting (and some probably did it already) to study how Steinbeck was inspired by the conventional imaging of Roman Charity, while he diverted from it.
The pounding of the rain decreased to a soothing swish on the roof. The gaunt man moved his lips. Ma knelt beside him and put her ear close. His lips moved again. "
Sure," Ma said. "You jus' be easy. He'll be awright. You jus' wait'll I get them wet clo'es off'n my girl." Ma went back to the girl.
"Now slip 'em off," she said. She held the comfort up to screen her from view.
And when she was naked. Ma folded the comfort about her. The boy was at her side again explaining, "I didn' know. He said he et, or he wasn' hungry. Las' night I went an' bust a winda an' stoled some bread. Made 'im chew 'er down. But he puked it all up, and then he was weaker. Got to have soup or milk. You folks got money to git milk?" Ma said, "Hush. Don' worry. We'll figger somepin out."
Suddenly the boy cried,
"He's dyin', I tell you! He's starvin' to death, I tell you." "Hush," said Ma.
She looked at Pa and Uncle John standing helplessly gazing at the sick man. She looked at Rose of Sharon huddled in the comfort. Ma's eyes passed Rose of Sharon's eyes, and then came back to them. And the two women looked deep into each other. The girl's breath came short and gasping. She said "Yes."
Ma smiled. "I knowed you would. I knowed!" She looked down at her hands, tight-locked in her lap. Rose of Sharon whispered, "Will-will you all—go out?" The rain whisked lightly on the roof. Ma leaned forward and with her palm she brushed the tousled hair back from her daughter's forehead, and she kissed her on the forehead.
Ma got up quickly. "Come on, you fellas," she called. "You come out in the tool shed." Ruthie opened her mouth to speak, "Hush," Ma said. "Hush and git." She herded them through the door, drew the boy with her; and she closed the squeaking door. For a minute Rose of Sharon sat still in the whispering barn. Then she hoisted her tired body up and drew the comfort about her. She moved slowly to the corner and stood looking down at the wasted face, into the wide, frightened eyes.
Then slowly she lay down beside him.
He shook his head slowly from side to side.
Rose of Sharon loosened one side of the blanket and bared her breast.
"You got to," she said. She squirmed closer and pulled his head close, "There!" she said. "There."
Her hand moved behind his head and supported it.
Her fingers moved gently in his hair. S
he looked up and across the barn, and her lips came together and smiled mysteriously.
John Steinbeck, The Grapes of Wrath