Or HaChaim on Numbers 16:14/אור החיים על במדבר ט״ז:י״ד

1 אף לא אל ארץ זבת חלב ודבש הביאותנו, "Moreover, you have not brought us to a land flowing with milk and honey, etc." Since they had already accused Moses of bringing them to a place where all one could do was to die, what was the point of accusing him that he had not brought them to a land flowing with milk and honey? Rashi gives a rather forced explanation to this question. Perhaps we can say that Datan and Aviram did not want to justify their refusal to go and see Moses merely because he had brought them to a place where all one could do was die. They implied that even if all he had done was not to bring them to a land flowing with milk and honey this would be sufficient reason for them to decline his invitation as Moses had failed to deliver on his promise. The words אף לא אל mean that this latter detail is already enough reason to decline his invitation. They were working up to their next argument: "will you put out the eyes of these men?" They implied that the fact that Moses had caused the people actual damage by marooning them in the desert was an additional reason for not coming to see him."

2העיני האנשים ההם תנקר, "should you gouge out the eyes of those men? we will not go up." They meant that they would rather have their eyes gouged out than to pay Moses the compliment of accepting his invitation. This comment revealed the very depth of their hatred. They preferred to have their eyes gouged out rather than to be granted a favour by the righteous Moses. No wonder Moses anger was greatly aroused!