Genesis 42:23

Surely we are being punished: The brothers believed that God was punishing them. They thought this because they now had to bring Benjamin to Egypt, even though their father did not want this. They connected this trouble with their past sin of selling Joseph to traders.

They began to see this as divine punishment (God judging wrong actions). The fear of divine punishment began to cause feelings of guilt that Joseph's cries for mercy and their father's tears had failed to produce (37:34–35).

Joseph did several unusual things to his brothers when they came looking for grain. The last time Joseph had been with them, they were filled with jealousy, hatred, and anger; they attempted to destroy their brother, and they deceived their father. Joseph put them through various tests, similar to the trying situations they had put him through, to see if they had changed.