He legislated a great method and way for all the world of how to treat a war captive, which, if humanity had applied, will find a way out of the captives' crisis in this brutal world. This crisis shocks anybody with feelings, a conscience or morality. 

That is because Muhammad had prevented the violation of human rights absolutely no matter what the justification might be.

So it's not acceptable neither to torture the captive physically or psychologically, it also not acceptable to curse, swear or even prevent him from food and drinks. On the contrary, Muhammad and his companions went to the point where they gave priority
to the captives in their food and drinks.