Genesis 42:24

‘And he turned himself away from them and wept, and he returned to them and spoke to them and took Simeon from among them and bound him before their eyes.'

Joseph overhears what they are saying and it brings tears to his eyes. Whether he actually goes out prior to speaking to them again through the interpreter we are not specifically told. Then he acts promptly. Simeon is placed in custody (‘bound') and they are made to watch. Whether ‘bound' includes being tied up with ropes we do not know, although as Joseph wanted to make the greatest possible impression it is quite possible.