وحكمه: أنه لو امتنع عن تناوله حتى قتل يكون آثماً
In this second category, refusing the necessary item until one dies is sinful.
The contrast is decisive. In the first category, refraining from a still-prohibited act may be rewarded. Here genuine necessity has made the relevant consumption permissible; allowing oneself to die rather than use a lawful survival measure is not the same kind of steadfastness.
This conclusion assumes real necessity, an actual life-preserving need, and an available concession. It should not be applied to ordinary inconvenience or unrelated circumstances.