In retrospect, the holy armament seems less appropriate than a variation of this:
Summon Weapon (Su): An aurumach can be armed in an instant by magically summoning a golden, Huge +3 halberd. When separated from the aurumach, the weapon vanishes. An aurumach can summon or dispel its own weapon as a free action.
So something like this?
Frostblade (Su): An air maiden can be armed in an instant by magically summoning a frost brand. When separated from the air maiden, the weapon vanishes. An air maiden can summon or dismiss its own weapon as a swift action.
This +3 frost greatsword sheds light as a torch when the temperature drops below 0°F. At such times it cannot be concealed when wielded, nor can its light be shut off. The air maiden receives resistance to fire 10 while wielding its frostblade.
A frost brand extinguishes all nonmagical fires in its area. As a standard action, it can also dispel lasting fire spells, but not instantaneous effects, though the air maiden must succeed on a dispel check (1d20+14) against each spell to dispel it. The DC to dispel such spells is 11 + the caster level of the fire spell.