The Gurus (preceptors) of the past taught only from experience; they loved their pupils and sought to correct their faults and failings, that is how their students lead happy and useful lives. When the pupils finally left the Guru's home, he exhorted them to follow two guidelines (Sutras) which were as essential for life as the two eyes (netras) - Speak the truth; Walk on the path of righteousness (Satyam vada, Dharmam chara). The Guru had the faith that the pupil (shishya) would take the advice to heart, for he himself was the living proof of their value and validity. The Guru always takes great care to remove from the heart of the pupil the weeds of evil habits and tendencies, and implant therein the seeds of love. He insists on spiritual discipline (sadhana) for purifying the pupils' minds and to render them strong enough to overcome temptations of all kinds. Virtue and character alone marks a truly educated person.
How were the old Gurus in the past traditions in that so holy culture where everything seems to turn around God only?
The Gurus (preceptors) of the past taught only from experience; they loved their pupils and sought to correct their faults and failings, that is how their students lead happy and useful lives.
We know that masters like the great Shankaracharya had a few disciples only and how do we understand such a school if it is taught only by experience?
Teacher is God and what does that exactly mean? If we identify inside with the teacher the wisdom flows in that inner view in a relationship of inner oneness and in the heart, the teaching is from heart to heart and in the mirror of consciousness and the inner view.
It needs a certain way of focus of the student to get to that inner oneness with his master and an example was Drona, he was a great teacher and the teacher of Arjuna and he was asked by someone else to be his teacher and he had his reasons why he refused to be his teacher, but he went and made a picture out of clay from Drona and thus revering him as his Guru he got all the knowledge and skills he wanted to get. He was worshipping his master and it is said that he became even stronger than Arjuna just by worship. That was for me always the best example of the power of devotion and how we can get self-knowledge and higher wisdom with a spiritual master.
Drona the teacher became to know of it, he asked that student for his thumb and he gave it to him, that way he made sure he couldn't use his skills the wrong way as he was not on the side of the friends, but the enemies. It was about great archery skills, without his right thumb he couldn't fight and use the weapons he got in such a way.