“Taking on a guru is not simply a fashion. One who is serious about understanding spiritual life requires a guru. A guru is a question of necessity, for one must be very serious to understand spiritual life, God, proper action, and one’s relationship with God. When we are very serious about understanding these subjects, we need a guru. We shouldn’t go to a guru simply because a guru may be fashionable at the moment. Surrender must be there, for without surrender we cannot learn anything. If we go to a guru simply to challenge him, we will learn nothing. We must accept the guru just as Arjuna accepted his guru, Śrī Kṛṣṇa Himself:
pṛcchāmi tvāṁ dharma-sammūḍha-cetāḥ
yac chreyaḥ syān niścitaṁ brūhi tan me
śiṣyas te ’haṁ śādhi māṁ tvāṁ prapannam
“Now I am confused about my duty and have lost all composure because of weakness. In this condition I am asking You to tell me clearly what is best for me. Now I am Your disciple and a soul surrendered unto You. Please instruct me.” (Bhagavad-gītā 2.7)
This is the process for accepting a guru. The guru is Kṛṣṇa’s representative, the former ācāryas’ representative. Kṛṣṇa says that all ācāryas are His representatives; therefore the guru should be offered the same respect one would offer to God.”
The Science of Self Realization : SSR 2: Choosing a Spiritual Master : What Is a Guru?