The brothers were defending themselves. Targum Pseudo-Jonathan on Genesis 43:7 preserves their explanation: "The man demanding demanded (to know) about us, and about our family, saying Is your father yet living? Have you a brother? And we informed him according to the word of these things. Could we know that he would say, Bring your brother down?"
Another doubled verb
The Aramaic paraphrase, which took its final form in the Land of Israel around the seventh or eighth century CE, preserves the emphatic Hebrew construction: sha'ol sha'al, "demanding demanded." Joseph had not asked casually. He had interrogated them about their father, about whether brothers still lived, about the structure of the family. The rabbinic tradition in Bereishit Rabbah 91:10, compiled in the Land of Israel around the fifth century CE, notes how pointed the questions were — precisely the questions a long-lost sibling would ask, dressed up as the questions a suspicious vizier would ask.
We answered according to the word of these things
The brothers' defense is essentially: we could not have lied. The Egyptian ruler was asking for specifics, and we gave him specifics. The implicit claim is that their honesty was itself the problem. If they had been more evasive, Benjamin would not now be required. But honesty, once spoken, becomes binding. The truth about their family composition is now the exact lever Joseph is using against them.
Could we know?
The final question — could we know that he would say, Bring your brother down? — is both defense and lament. They could not have anticipated the demand. They answered the questions they were asked. And yet, the rabbinic tradition notes, this is the first time in the Joseph cycle that the brothers are held accountable for their own truthful words. Truth, too, has consequences.
The takeaway
Sometimes the truth we tell in one moment becomes the test we are given in the next. Honesty does not release us from the story it writes.