Take double money— i.e.. Both the money which was returned in the mouths of the sacks, and as much more, to buy a second supply of corn. See Genesis 43:21-22.
Related Commentaries of Genesis 43:12
Genesis 43:12
12 And take double money in your hand; and the money that was brought again in the mouth of your sacks, carry it again in your hand; peradventure it was an oversight: