Accepting the bona fide spiritual master as one’s life and soul and worshipable deity, the disciple should learn from him the process of pure devotional service. The Supreme Personality of Godhead, Hari, the soul of all souls, is inclined to give Himself to His pure devotees. Therefore, the disciple should learn from the spiritual master to serve the Lord without duplicity and in such a faithful and favorable way that the Supreme Lord, being satisfied, will offer Himself to the faithful disciple.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
तत्र भागवतान् धर्मान् शिक्षेद्गुर्वात्मदैवतः । अमाययानुवृत्त्या यैस्तुष्येदात्माऽऽत्मदो हरिः
tatra bhāgavatān dharmān śikṣedgurvātmadaivataḥ | amāyayānuvṛttyā yaistuṣyedātmā''tmado hariḥ
SB 11.3.22