Rashi on Genesis 42:24/רש"י על בראשית מ״ב:כ״ד

1ויסב מעליהם AND HE TURNED AWAY FROM THEM — He moved some distance away from them so that they should not see him weeping.

2ויבך AND HE WEPT because he heard that they regretted their past conduct to him.

3את שמען SIMEON — he had cast him into the pit and it was he who had said to Levi “Behold, this dreamer cometh” (Tanchuma Yashan 1:10:17). Another explanation is: It was Joseph’s intention to separate him from Levi lest the two of them might conspire to kill him.

4ויאסור אתו לעיניהם AND HE BOUND HIM BEFORE THEIR EYES — He only kept him in bonds whilst he was before their eyes, but as soon as they departed he freed him and gave him food and drink (Genesis Rabbah 91:8).