A teacher (àcariya or garu, Sanskrit guru) is a person who imparts skills or knowledge, and a disciple (sàvaka) is one who learns from a teacher. In some religions, and even within the Vajrayàna branch of Buddhism, the disciple is expected to dedicate himself or herself totally to the teacher and obey unquestioningly. This is very much at odds with what the Buddha both taught to and required from his disciples. He advised that before learning under a teacher, and even while receiving instruction, the disciple should maintain a respectful but questioning and discriminating attitude. It is not necessary to assume that someone is a worthy just because they or others say they are. One should investigate (vãmaüseyya) the teacher by watching and listening to see if his or her behaviour is consistent with what is being taught. Continuing to investigate over a period of time, the disciple should try to see if the good qualities the teacher appears to have are internalized or whether they are only the result of making an effort or trying to impress. Other things that might indicate a teacher's true worth are seeing if they act differently in public than in private and whether they are affected by fame and success (M.I,318-20).
The Buddha approved of respect and reverence by a disciple towards a teacher. He said: `A teacher should look upon his student as a son. A student should look upon his teacher as a father. United by this mutual reverence and deference and living in communion with each other, both will achieve increase, growth and progress in this Dhamma and discipline'(Vin.IV,45). `It is proper for the disciple to serve the teacher with love' (M.III,264). However, the truly sincere teacher will want the disciple to attain the same level of virtue and knowledge as himself or herself or even surpass it, and this can only be done in an environment where questioning and free expression are encouraged.