John Gill Commentary Genesis 42:12

"And he said unto them, Nay, but to see the nakedness of the land ye are come." — Genesis 42:12 (ASV)

And he said to them, nay
This argument will not do, I am not to be put off with such words as these; if you can produce no better proof of your being honest men than this, or give no better account of yourselves, I must abide by it, that, to see the nakedness of the land you are come ;
this he urged in order to get a further account from them of their family and the state of it, which he was anxious to know.