An authentic Teacher has done more than just acquiring all the necessary knowledge by integrating its different aspects through its personal experience. An authentic Teacher is also filled with wisdom and a boundless compassion, always keeping a very humble and simple attitude.
Such a Teacher is the holder of an authentic lineage dating back to the Buddha himself.
This spiritual friend stands as a true protection against negative experiences and a reliable guide on the positive way, for one’s and other’s sakes. Once he has been found and it’s authenticity confirmed, he remains a guide to be fully trusted.
Trust towards the Teacher is most important as it makes experiences on the Path much simpler and more direct.
Parents, friends and ordinary teachers cannot help you achieve liberation, for they are not free from samsara themselves. To attain enlightenment you must have the guidance of an authentic spiritual master. Without a spiritual master you will get nowhere, like a passenger in an airplane without a pilot.
So do not overestimate your capacities. Having sought and found a qualified master endowed with wisdom, compassion and ability, follow him with confidence, receive his instructions and practice them with diligence.
RELYING ON A SPIRITUAL TEACHER, WHOSE PRESENCE CREATES CONDITIONS FAVORABLE TO YOUR PROGRESS
6 Through reliance on a true spiritual friend one's faults will fade
And good qualities will grow like a waxing moon --
To consider him even more precious
Than one's own body is the practice of a bodhisattva
To achieve liberation from samsara and attain the omniscience of enlightenment would be impossible without following an authentic, qualified spiritual teacher. Such a teacher always acts, speaks, and thinks in perfect accord with the Dharma. He shows you what you have to do to progress successfully on the path, and what obstacles you will have to avoid. He encourages you to concentrate on practicing the Dharma above all, and to do only what is virtuous and beneficial. He helps you give up all unsuitable conduct without hypocrisy, and he reminds you to be aware of impermanence, and to stop clinging to samsara.
An authentic teacher is like the sail that enables a boat to cross quickly over the ocean. If you trust his words, you will easily find your way out of samsara -- and that is why the teacher is so precious. It is said, "The merit of offering a drop of oil to a single pore of the teacher's body surpasses the merit derived from making countless offerings to the buddhas."
The Heart of Compassion: The Thirty-Seven Verses on the Practice of a Bodhisattva