So I always choose my funny screen name as answer, and seldom tell them that this red-yellow lunatic (note that he IS from another world) is actually the avatar. But a humble person would also do so.
I think this is an issue the feudal lands maker should think about if they implement a karma system. If the avatar tells his birth name, then he's humble. If he is boasting out his avatarhood, he's exploding from pride - the antithesis to humility. So please keep that in mind. The karma should actually increase if the avatar gives out his birth name - unless a npc want's him to decide, so that it is a question of honor.
If the guardian calls on the avatar "to tell them", he musn't do so - because his humility keeps him on the ground.
But if some dude asks "Are you the avatar?" he has to respond honestly. Only if he lies then, he should loose karma.
But there could be other decision problems from the like: if the avatar lies, he will be rescuing someone, who dies if he speaks the truth - now that would be very twisted! If the avatar prefers the humble path, he would lie, knowing, that he would do good in the end, and overcome his own pride, that is to excel in all virtues.
Is this some sort of theological problem? Maybe we can make an avatar schism


Maybe there could be different spells for the different sides of the virtue might! And a sidequest for the avatar is obtaining his personal light saber, i.e. forge/obtain a magical sword on his own (it glows), a precursor to the laser tecnique!
MfG
Ey Du