Genesis 42: 5-8
So Israel’s sons were among those who went to buy grain, for there was famine in the land of Canaan also.
Now Joseph was the governor of the land, the person who sold grain to all its people. So when Joseph’s brothers arrived, they bowed down to him with their faces to the ground. As soon as Joseph saw his brothers, he recognized them, but he pretended to be a stranger and spoke harshly to them. “Where do you come from?” he asked.
“From the land of Canaan,” they replied, “to buy food.”
Although Joseph recognized his brothers, they did not recognize him.