The outer Guru appears to tell us about the reality of the Self, who is the inner Guru. With our defective vision we cannot see or experience for ourselves that this is true. The inner Guru pulls us towards the Self and establishes us there. The inner Guru is waiting at all times to perform this function but he cannot begin until we turn our attention towards him.
It is the outer Guru who tells us, ‘Turn within. Put your attention on the inner Guru and let him pull you back into your source.’
In addition to giving these instructions, the outer Guru transmits his grace to us, cleans our minds, and pushes them towards the inner Guru, the Self.
All Gurus are the Self. All Gurus are formless. And all Gurus are ultimately one and the same. The outer forms of the Guru may appear differently to different people but there is really only one Guru, and that Guru is the Self.
When we reach spiritual maturity, the Self manifests to us in the form of a Guru in order to help us to make further progress with our sadhana.
The relationship with the outer Guru lasts as long as it is necessary. It lasts until the sishya [disciple] knows from direct experience that the Self alone exists. In my case a time came when it was no longer physically possible for me to be with the form of the Guru. Bhagavan severed the physical relationship because he wanted me to be aware of him as he really is. When you pass your exams at school, you graduate to the next class. We cannot enter the same class again. I graduated from regarding Bhagavan as a form and came to regard him as the formless Self. After that I was never given the chance to have a relationship with Bhagavan’s physical form again.
Other disciples were treated differently. The Guru does not give the same treatment to all. He looks at the maturity and the predilections of each disciple and gives an appropriate sadhana to each one. For example, Bhagavan encouraged some of his devotees to sing devotional songs because that was an appropriate path for them. In my case he encouraged me to be aware of the formless Self.