The caster creates a physical manifestation of a whip that they are holding. So yes, fire shield would work on that because they are wielding a weapon used in the attack, even if the weapon is temporary.Okay, you can create exceptions to fire shield by adding the requirement that there must be a physical connection between the caster and the attacker for the spell to work. This would also except Mordenkainen's sword from triggering damage from fire shield.
What about thorn whip? Would you consider the magically created whip to constitute a physical connection between the attacker and the target?
How do you interpret this:That's kind of insulting. It assumes your intepretation of the rule is the one true way, and you ok with people changing it, but your reading in the one one that's "right". Others are saying that the rule can be interpreted either way, and both are acceptable.
*Natural language and allUnder Weapons:
The Weapons table shows the most common weapons used in the fantasy gaming worlds, their price and weight, the damage they deal when they hit, and any special properties they possess.See, weapons can hit too.
The rules don't say that.Which it doesn't, the cleric attacks with it.
Arrows can be used in traps and require no creature to roll an attack roll.Another example from the rules of a weapon hitting:
Poison, Basic. ... A creature hit by the poisoned weapon or ammunition must make a DC 10 Constitution saving throw or take 1d4 poison damage.Spell effects are not special in this way.
Certainly it does, which I have highlighted in the spell repeatedly yet you seem determined to ignore.The rules don't say that.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.