I understand that Clerics are bound by their ethos to "never shed blood", and I understand that clerics were based on tropes from the 70's, but does that rule still apply to cleric/thieves?
From what I understand, the only weapons a cleric/thief can use to back-stab is with a club (or a stave, I think?). Was this their intention? I can't imagine, for example, a cleric/thief of an evil god limiting himself/herself from using edge weapons to set an example. I imagine they are not too worried about keeping up appearances.
Best Answer
Your example sans thief is answered on page 34: “Not all mythoi are opposed to the shedding of blood. Indeed, some require their priests to use swords, spears, or other specific weapons. A war deity might allow his priests to fight with spears or swords.”
It then gives a list of suggested deities (by “mythoi”, by which they mean things like “death”, “hunt” and so on).
In stock AD&D 2e, there is no multi-class cleric/thief. However, there are other cleric combinations, and “Regardless of his other classes, a multi-classed priest must abide by the weapon restrictions of his mythos. Thus, a fighter/cleric can use only bludgeoning weapons (but he uses the warrior combat value).” (p. 45)
So it isn’t also being a thief that would alter a cleric’s weapon choices, but their deity.
Dual-class is more restrictive, but the basic rule is that “the character must still abide by the restrictions of whichever class he is using at the moment.” The example is, almost fortuitously, a cleric who changes to fighter, but the example does not mention weapon choice.