Genesis 44:1-34

“So please, my lord, let me stay here as a slave instead of the boy, and let the boy return with his brothers. 34For how can I return to my father if the boy is not with me? I couldn’t bear to see the anguish this would cause my father!”
Joseph wanted to see if his brothers' attitudes had changed for the better, so he tested the way they treated each other. Judah, the brother who stepped forward with the plan to sell Joseph, now stepped forward to take Benjamin's punishment so Benjamin could return to their father. This courageous act convinced Joseph that his brothers had dramatically changed for the better.

Taken from the NLT Life Application Study Bible