Sforno on Genesis 42:28/ספורנו על בראשית מ״ב:כ״ח

1מה זאת עשה אלוקים לנו?. Why would G’d put such ideas in the heart of a person (the ruler) who described himself as “G’d-fearing?” This is also why later, after the goblet had been found in the sack of Binyamin, the brothers offered themselves as slaves to Joseph, feeling that this would be the appropriate punishment for their having sold Joseph into slavery. (43,18). Still, they felt that selling Joseph had not been intended to be detrimental to him; rather seeing they had considered themselves endangered by him as a רודף, they considered this at the time as mild compared to killing him, which they thought they were entitled to do. The very fact that they had not killed him at the time they had considered as proof of their brotherly love