Originally Posted by Andezzar
I think Vaern interpreted "knowledge of the spell contained therein" as meaning having the spell on the list of known spells for the user. This indeed is unnecessary. You do need to which spell(s) the staff has available however.
What he said. My question is assuming that an identify spell has already been used on the staff being activated, or that it was purchased from an NPC who had sufficiently informed the character of the staff's abilities. The spells contained within a wand or staff do not need to be on the character's "spells known" list, only his class spell list.