Genesis 42:24
And he turned himself about from them, and wept; and returned to them again, and communed with them, and took from them Simeon, and bound him before their eyes. And he turned himself about from them, and wept; and returned to them again, and communed with them, and took from them Simeon, and bound him before their eyes.
During a famine Jacob's sons journeyed from Canaan to Egypt to buy grain, where Joseph recognized them though they did not recognize him. As they bowed before him, the scene recalled his earlier dreams.
They spoke openly to one another because Joseph spoke to them through an interpreter, so they did not know he understood them. On the third day he had proposed that they should live and prove themselves honest by leaving one of them bound in prison and bringing their youngest brother to verify their words, which they had agreed to though they had little hope their father would let Benjamin go.
Then the brothers admitted their guilt over selling Joseph and their cruelty toward him, recalling the anguish of his soul when he pleaded with them and concluding that their present distress had come upon them for that reason. In that exchange Reuben reminded them that he had warned them not to sin against the child and that his blood was now being required. Hearing this admission of guilt, Joseph was overcome with emotion and turned away from them and wept.
After weeping, he returned to them and spoke with them. He then took Simeon and had him bound before their eyes to be kept in prison. Simeon was selected because he had led the others and been the chief instigator in the cruel treatment of Joseph.