When cast upon an item, this spell allowed a non-magical item to receive the magical energy of a spell while still being its intended target. While it didn't enchant the item itself, like the arcane spell, it allowed an item to hold an enchantment, or dweomer typically from one or several focal stones.
Eternal flame could also be cast, by touch, on the bodies of living, dead or undead mammals. The next spell affecting the target, with a few exceptions, would have maximum effect in all aspects, including damage, duration, intensity, etc. The exceptions were any enchantment/charm, or Illusion/phantasm spells. If the volume of the target body was more than twice that of the caster, the spell would fail.