Anyone who has ever played D&D surely knows of the holy avenger, the mighty magical sword whose true power manifests only in the hands of a paladin.
For purposes of a campaign to be set in the Forgotten Realms, I am attempting to ascertain where the notion of the paladin wielding a special sacred weapon first crossed into official Realms material. The Realms have experienced several in-narrative events created to coincide with, and explain, rules changes that came with each new edition of D&D -- the (first) Sundering, the Time of Troubles, etc. The functions of magic, and magic items, have often changed through these events. To understand how (or if) the holy avenger has changed in the Realms, I need to identify its starting point.
In case it helps, I trace the holy avenger back to early editions of D&D where it was presented as but one token of a broader type: the holy sword. The first printed appearance of the holy sword I can find is in Supplement 1: Greyhawk, which presented the holy sword as if it were a class feature part-and-parcel of the paladin:
Paladins with any form of "Holy Sword" are virtually immune to all magic (see MONSTERS & TREASURE, MAGIC & TREASURE, Swords).
(See p. 8.) Two kinds of holy sword were offered there, namely the holy sword +5 and the sword of sharpness. (See pp. 46-47.) In AD&D 1e, the DMG likewise described the holy avenger (technically named "Sword, +5, Holy Avenger") as "a holy sword." (See p. 165.) And the 1e PHB again treated the holy sword like a class feature, though without actually describing the properties of the weapon itself:
If a paladin has a "Holy Sword" (a special Magic Sword which your referee is aware of and will explain to you if the need arises), he or she projects a circle of power 1" in diameter when the Holy Sword is unsheathed and held; and this power dispels magic . . . at the level of magic use equal to the experience level of the paladin.
(p. 22; emphasis mine.) In 2e, the PHB (see pp. 27-28) did essentially the same. At least two 2e volumes specific to the Realms go on to mention holy avengers (though not holy swords):
Faiths & Avatars mentions holy avengers in reference both to characters with the Crusader kit (p. 184), and to the weapon carried by the avatar of Torm: "Duty's Bond, a massive two-handed holy avenger +5 with all the powers of a sun blade as well" (p. 163).
Warriors and Priests of the Realms mentions the holy avenger, but curiously only in reference to evil Crusader characters. (See p. 64.)
Both Faiths & Avatars and Warriors and Priests of the Realms show publication dates in 1996.
However, given that Faiths & Avatars couches its write-up of Torm in terms of his activity during the Time of Troubles, it is conceivable that an earlier-published Realms novel might have portrayed Torm in his mortal life as a paladin wielding Duty's Bond or some like weapon.
Are these the earliest-published references to holy avengers (or holy swords) in the Realms? Or is there an earlier origin, perhaps in 1e rulebooks or an early novel?