Authority

Any question that is put forward may be answered by quoting the authority, and that satisfies the saner section. That is the system even in the law court. The best lawyer gives evidence from the past judgement of the court without taking much trouble to establish his case. This is called the parampara system and learned authorities follow it without manufacturing rubbish interpretations.
Srimad Bhagavatam 2.10.51purport

Whenever we receive knowledge we are accepting an authority on that particular subject. Whether it be our professor at university or a supervisor at our workplace, we all require to learn from one who is already wise to the subject. But who is a suitable authority to enlighten us in the highest knowledge of reality and our intimate place therein? This is guru. Guru does not just mean teacher, but a direct representative of the absolute truth. Guru is a manifestation of the unlimited mercy of Krishna with the mission to redirect humanity and bestow the highest wealth of pure loving service. When one submissivly inquires and renders service to please guru then one can learn all by his grace. When guru passes on knowledge to such a disciple, he does not interpret or give his own opinion. Nor does he add or exclude anything. He acts simply as a transparent medium for transcendental knowledge to descend. A postman simply delivering the mail. Thus he is the perfect representative. A perfect teacher is one who is a perfect student, always learning from his authorities.

Yet sometimes we declare that we need no guru, guide or book to understand reality. We claim ourselves capable of understanding all by our own abilities. We do not want to accept any authority, "We are our own authority!!" To be free and rebellious is cool, is it not? Certainly we idolize those who stand on their own, but being under natures laws, how independent are they? Does freedom mean that we just follow our minds constantly changing ideas, regardless of advice?

Whilst respecting those bold enough to stand alone, we must also recognize our weaknesess.

It is described that we have 4 shortcomings that prevent us from independently understanding reality. We have imperfect senses, we commit mistakes, we are prone to illusion and we have a cheating propensity. Besides these, how can the unlimited absolute truth be conceived by our limited mind.

Therefore, understanding our tiny size in relation to the bigger picture, it would be in our best interest to approach an expert in these topics. Guru, acting like a judge, lives in harmony with his teachings. He resonates with the absolute truth as he is dedicated to the will of the supreme. His character is pure, free from duplicity and he lives a controlled life of wisdom and religiousity. He is qualified to reveal truth as he is directly perceiving truth. His life is absolute truth, he is the servant of Krishna, the supreme absolute truth.