Genesis 42:1 - The Popular Commentary by Paul E. Kretzmann

Now when Jacob saw that there was corn in Egypt, having undoubtedly gotten the information from his Canaanite neighbors, many of whom were merchants, Jacob said unto his sons, Why do ye look one upon another? The mention of Egypt caused the brethren to look upon one another with a helpless and suspicious questioning, for their conscience reminded them of the fact that Joseph had been sold into Egypt.