No.

The spellcaster completes the spell, and you are engulfed in dark red flames. You howl loudly in pain and fall to the ground, your limbs tossing wildly as you try to put out the fire searing through your flesh.

The spellcaster laughs at you. "That's not gonna work, pup. That shit's hellfire. It can't be put out by mundane means." He then addresses the knight. "Go smack it dead now that it's defenseless. You need all the health you can absorb."

You can't even concentrate enough to figure out where the knight is. The fire hurts too bad. Fire is of course never pleasant, but it feels far more severe than usual. It might just be because, as the spellcaster said, it's hellfire. But you also suspect that the debuff he cast on you lowered your fire resistance even more. Your health diminishes fast, and you can't seem to do anything to stop it.

You feel the knight's sword pierce into your abdomen, and momentarily your wails of torment grow slightly stronger. However, the knight too yelps in pain.

"Fuck! That burned!" he complains.

"Well of course it does if you try to thrust your sword in to the hilt!" the spellcaster says, annoyed. "Hellfire both hurts the target and gives it kind of this fire aura. It's called balancing. It can't be put out, so it needs some other downside."

"And how was I supposed to know?!"

"I didn't think you'd get that intimate with it like an idiot!"

Your pain remains near unbearable, but you still manage to understand most of the heroes' bickering. Apparently this dreadful spell gives you a combat advantage... Maybe, if you could fight through the pain... You could use it.