Guru's role in souls journey

The soul journeys across so many multivarious experiences in different dimensions. What is the role of Guru or master in the journey of a soul? He looks like a middleware in this Holy trinity of creation. He is a transformer who brings about this transformation from,  me (self) - > beloved (Guru) - >ME (SELF)
He takes our lower self to our higher self.
So the journey begins and ends in the self, from self (i)  to the SELF (which encompasses the entire universe).
He is the middleware in ignorance - >knowledge - >total ignorance.