People think Gnani is to refer to a Saint or religious head but the true import of this word Gnani is one who has realized the fact that the self is not physical but it is the soul and Soul is the innermost Self and soul is ultimate truth. the soul is in the form of consciousness .
A simple point is that one is a Gnani whose "ego" is totally absent because he is fully aware the consciousness is the true self and he abides in the Soul, the innermost self, which is ultimate reality.
A Gnani has no real teaching, and has nothing new to add to us in the conventional sense. This is because he sees everything as the manifestation of the Consciousness [Self] and there is no difference in their perceptions of the world of forms. To them, the individuals are no different from them. They work on their own way and guide the fellow seekers to move ahead without expecting anything in return.
The one who believes in re-incarnation cannot be Gnani. A Gnani his-self with the consciousness therefore the question of birth, life, death and world does not arise. Gnani don't initiate people into any practice of path, and in fact they exhort people to go beyond the mind. They only prescribe discrimination between the Unreal and the Real.
The Saints and Spiritual teachers may not fit the description of a Gnani. To compare a religious guru or god men or scriptural scholar as Gnani is too farfetched.