And as one of them opened his sack
According to the Targum of Jonathan and Jarchi, this was Levi; but Aben Ezra thinks it is more likely to be Reuben the firstborn, who was one, that is, the first of them: to give his ass provender in the inn;
at which they lay very probably the first night of their journey; a good man regards the life of his beast, and takes care of that as well as of himself, and generally in the first place: he espied his money;
the money which he paid for his corn: for, behold, it [was] in his sack's mouth;
just as he opened it.