You are reading a tafsir for the group of verses 12:60 to 12:61

And, along with it, he gave them a warning as well:

فَإِن لَّمْ تَأْتُونِي بِهِ فَلَا كَيْلَ لَكُمْ عِندِي وَلَا تَقْرَ‌بُونِ

Still, if you do not bring him to me, then you deserve no measure from me [ because it will prove that you have lied to me, and thus ], nor shall you come even close to me. - 60

Then, he made a secret arrangement as well. He ordered his young workers on the job to collect the cash, jewelry and any other articles paid by his brothers as the cost of the grains, and tie it up secretly with their supplies in the camel-packs in a way that they should remain unaware of it while there - so that, when they open their packs after having arrived home, and find their cash and jewelry back in their hands, they may have a reason to return for grains once again.