Srimad-Bhagavatam: Canto 7 - Chapter 1 - Verse 26
यस्य साक्षाद्भगवति ज्ञानदीपप्रदे गुरौ ।मर्त्यासद्धी: श्रुतं तस्य सर्वं कुञ्जरशौचवत् ॥ २६ ॥
yasya sākṣād bhagavatijñāna-dīpa-prade guraumartyāsad-dhīḥ śrutaṁ tasyasarvaṁ kuñjara-śaucavat
The spiritual master should be considered to be directly the Supreme Lord because he gives transcendental knowledge for enlightenment. Consequently, for one who maintains the material conception that the spiritual master is an ordinary human being, everything is frustrated. His enlightenment and his Vedic studies and knowledge are like the bathing of an elephant.
It is recommended that one honor the spiritual master as being on an equal status with the Supreme Personality of Godhead. Sākṣād dharitvena samasta-śāstraiḥ. This is enjoined in every scripture. Ācāryaṁ māṁ vijānīyāt. One should consider the ācārya to be as good as the Supreme Personality of Godhead. In spite of all these instructions, if one considers the spiritual master an ordinary human being, one is doomed. His study of the Vedas and his austerities and penances for enlightenment are all useless, like the bathing of an elephant. An elephant bathes in a lake quite thoroughly, but as soon as it comes on the shore it takes some dust from the ground and strews it over its body. Thus there is no meaning to the elephant’s bath. One may argue by saying that since the spiritual master’s relatives and the men of his neighborhood consider him an ordinary human being, what is the fault on the part of the disciple who considers the spiritual master an ordinary human being? This will be answered in the next verse, but the injunction is that the spiritual master should never be considered an ordinary man. One should strictly adhere to the instructions of the spiritual master, for if he is pleased, certainly the Supreme Personality of Godhead is pleased. Yasya prasādād bhagavat-prasādo yasyāprasādān na gatiḥ kuto ’pi.