Bhakti Sandarbha 212-213 : The Spiritual Guru is the Manifestation of Bhagavān
These two anucchedas are the conclusion of the guru-tattva-prakaraṇa, continuing the emphasis on the non-difference of the guru with Bhagavan raised in the previous anucchedas. Again by the a fortiori argument, if the vyavahārika guru is to be accepted as a manifestation of the Divine, then how much more it is true for the paramārthika guru. If one does not recognize the divine purpose of the teachings one has received or the guru's being the divine manifestation of God's grace, then whatever he has learned from him loses its potency. This will be further explained in Anuccheda 286.
The Spiritual Guru is the Manifestation of Bhagavān
This being the case, it is all the more incumbent on those pursuing the path of spiritual realization to have such feelings toward their guru, as Śrī Nārada told Yudhiṣṭhira:
यस्य साक्षाद्भगवति ज्ञानदीपप्रदे गुरौ।
मर्त्यासद्धीः श्रुतं तस्य सर्वं कुञ्जरशौचवत्॥
एष वै भगवान् साक्षात् प्रधानपुरुषेश्वरः।
योगेश्वरैर्विमृग्याङ्घ्रिर्लोको यं मन्यते नरम्॥
One who considers as a mortal being the guru, who is directly Bhagavān illuminating the heart with the lamp of wisdom, has a perverted understanding, and all his scriptural knowledge is futile, like the bathing of an elephant.
He is directly Bhagavān, the ruler of the primordial nature and the living beings, whose feet are sought by great masters of yoga. Yet out of delusion worldly people think of him as a human being. (SB 7.15.26-27)
एष श्रीकृष्णलक्षणोऽपि। ततः प्राकृतदृष्टिर्न भगवत्तत्त्वग्रहणे प्रमाणमिति भावः॥
In the second of these two verses, the pronoun “he” (eṣaḥ) refers back to its antecedent from the previous verse, the guru. It carries the sense: “this guru, even though characterized as Kṛṣṇa Himself” [is viewed as an ordinary human]. Therefore, material vision is not a valid criterion for understanding the Supreme Reality.
॥७.१५॥ श्रीनारदो युधिष्ठिरम्॥२१२॥
Bhagavān has appointed various devas for looking after the managerial affairs of the universe, but the department of spiritual education is under His own control. Therefore, He Himself takes the form of the guru to teach conditioned beings the way to reach Him. Uddhava also confirms this elsewhere in the Bhāgavatam (11.29.6). Therefore, Śrī Nārada here twice calls the guru Bhagavān directly, sāksād bhagavān. If one considers the paramārthika guru to be a material being, then he will not get spiritual knowledge from him because spiritual knowledge cannot come from a material person. The student has to have this faith or the transfer of knowledge will not take place. One's achievement is parallel to his or her faith, yādṛśī bhāvanā yasya siddhir bhavati tādṛśī.
One may object that it is impossible to consider the guru as Bhagavān. He appears and functions like any other human being. The reply is that in this matter śāstra alone is the authority. When Kṛṣṇa appeared on earth, He also looked and acted like other human beings. Though exceptional in many ways, outstandingly beautiful and qualified and so on, He too ate, slept, felt hungry, and passed urine (Cf. 10.8.31); He married and produced children. But on the authority of śāstra we accept Him as Svayam Bhagavān. Therefore, the guru should also be recognized on the same authority.
The modifier sākṣāt signifies that guru should not even be considered a partial manifestation of Bhagavān.
The Guru is Most Dear to Bhagavān
शुद्धभक्तास्त्वेके श्रीगुरोः श्रीशिवस्य च श्रीभगवता सहाभेददृष्टिं तत्प्रियतमत्वेनैव मन्यन्ते, यथा (भा. ४.३०.३८)—
But some pure devotees of a particular class consider the guru and Śiva to be non-different from Bhagavān simply because they are most dear to Bhagavān. The Pracetas conveyed this idea to Bhagavān [who had appeared before them in His eight-armed form]:
वयं तु साक्षाद्भगवन् भवस्य
प्रियस्य सख्युः क्षणसङ्गमेन।
सुदुश्चिकित्स्यस्य भवस्य मृत्यो-
भिषक्तमं त्वाद्य गतिं गताः स्म॥
टीका च—"तव यः प्रियः सखा, तस्य भवस्य। अत्यन्तमचिकित्सस्य भवस्य जन्मनो मृत्योश्च भिषक्तमं सद्वैद्यं त्वां गतिं प्राप्ताः॥" इत्येषा। श्रीशिवो ह्येषां वक्तॄणां गुरुः॥O Bhagavān, by a moment’s association with Your dear friend Śiva, we have directly attained You as our ultimate destination and as the topmost physician for treating the virtually incurable disease of repeated birth and death in material existence. (SB 4.30.38)
Śrīdhara Svāmī also comments: “By the association of Śiva, who is Your dear friend, we have attained You, the most qualified doctor to treat the completely incurable disease of repeated birth and death.” Śiva is the guru of the Pracetas, who spoke this verse.
॥४.३०॥ श्रीप्रचेतसः श्रीमदष्टभुजपुरुषम्॥२१३॥
Commentary by Satyanarayana Dasa Babaji Maharaja
Up until now it has been said that the guru is Bhagavān and should be respected like that. In fact one of the very popular verses in India about the guru goes as follows:
gurur brahmā gurur viṣṇur guruḥ devo maheśvaraḥ
gurur eva paraṁ brahma tasmai śrī gurave namaḥ
The guru is Brahmā. He is Viṣṇu. He is Śiva himself. Indeed, the guru alone is the Supreme Reality. I bow down to such a guru.
Now Śrī Jīva reveals even a higher secret. That is the principle of oneness and difference simultaneously. The guru is to be respected as a manifestation of Bhagavān, yet he is a dearmost devotee of Bhagavān. His oneness with Bhagavān is because of love. He is not ontologically one with Him. This is the understanding of great devotees like Śrī Viśvanātha Cakravartī, who has sung,
uktas tathā bhāvyata eva sadbhiḥ
kintu prabhor yaḥ priya eva tasya
vande guroḥ śrī-caraṇāravindam
All the scriptures describe the guru as Kṛṣṇa and saintly people honor him in this way. But I know him to be His dear devotee. I bow down to the feet of Śrī Guru. (Gurvaṣṭakam 7)
This is also the relation between Śiva and Kṛṣṇa. In many places Śiva is depicted as non-different from Kṛṣṇa or Viṣṇu, yet he is a great devotee of Viṣṇu. The oneness between them is because of love. Therefore, the guru and Śiva should be honored as great devotees of Kṛṣṇa. That is very pleasing to Bhagavān. To accept the guru as Bhagavān directly will go against the practice of rāgānugā bhakti because in this type of devotion one serves Kṛṣṇa under the guidance of a guru who is himself a devotee. The mood is to be the servant of a servant and not a direct servant of Kṛṣṇa. If the guru is accepted as Bhagavān directly then there can be no rāgānugā.
The present verse is spoken by the Pracetas who accepted Śiva as their guru, seeing him as both a great devotee and friend of Bhagavān.
Bhakti Sandarbha 210-211: The Mantra Guru is Also Compulsory
Bhakti Sandarbha 209 : The bhajana-śikṣā guru is also necessary
Bhakti Sandarbha 208 : There is No Possibility of Knowledge Without Guru
Bhakti Sandarbha 207 : Dīkṣā Guru is Only One
Bhakti Sandarbha 206 : The śravaṇa- and bhajana-śikṣā-gurus are usually the same person
Bhakti Sandarbha 204-5: Proper Deliberation on Śāstra Brings About Śraddhā in Bhajana
Bhakti Sandarbha 203: The Guru Should not be Greedy
Bhakti Sandarbha 202 : The Necessity of Guru : Different Types of Sadhus Give Different Types of Bhakti