Srimad Bhagavatam Canto 10, Chapter 02, Text 31

SB 10.2.31

svayam samuttirya sudustaram dyuman
 bhavarnavam bhimam adabhra-sauhrdah
bhavat-padambhoruha-navam atra te
 nidhaya yatah sad-anugraho bhavan
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
O Lord, who resemble the shining sun, You are always ready to fulfill the desire of Your devotee, and therefore You are known as a desire tree [vañcha-kalpataru]. When acaryas completely take shelter under Your lotus feet in order to cross the fierce ocean of nescience, they leave behind on earth the method by which they cross, and because You are very merciful to Your other devotees, You accept this method to help them.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
This statement reveals how the merciful acaryas and the merciful Supreme Personality of Godhead together help the serious devotee who wants to return home, back to Godhead. Sri Caitanya Mahaprabhu, in His teachings to Rupa Gosvami, said:
brahmanda bhramite kona bhagyavan jiva
 guru-krsna-prasade paya bhakti-lata-bija
(Cc. Madhya 19.151)
One can achieve the seed of bhakti-lata, devotional service, by the mercy of guru and Krsna. The duty of the guru is to find the means, according to the time, the circumstances and the candidate, by which one can be induced to render devotional service, which Krsna accepts from a candidate who wants to be successful in going back home, back to Godhead. After wandering throughout the universe, a fortunate person within this material world seeks shelter of such a guru, or acarya, who trains the devotee in the suitable ways to render service according to the circumstances so that the Supreme Personality of Godhead will accept the service. This makes it easier for the candidate to reach the ultimate destination. The acarya’s duty, therefore, is to find the means by which devotees may render service according to references from sastra. Rupa Gosvami, for example, in order to help subsequent devotees, published such devotional books as Bhakti-rasamrta-sindhu. Thus it is the duty of the acarya to publish books that will help future candidates take up the method of service and become eligible to return home, back to Godhead, by the mercy of the Lord. In our Krsna consciousness movement, this same path is being prescribed and followed. Thus the devotees have been advised to refrain from four sinful activities illicit sex, intoxication, meat-eating and gambling and to chant sixteen rounds a day. These are bona fide instructions. Because in the Western countries constant chanting is not possible, one should not artificially imitate Haridasa Thakura, but should follow this method. Krsna will accept a devotee who strictly follows the regulative principles and the method prescribed in the various books and literatures published by the authorities. The acarya gives the suitable method for crossing the ocean of nescience by accepting the boat of the Lord’s lotus feet, and if this method is strictly followed, the followers will ultimately reach the destination, by the grace of the Lord. This method is called acarya sampradaya. It is therefore said, sampradaya-vihina ye mantras te nisphala matah (Padma Purana). The acarya sampradaya is strictly bona fide. Therefore one must accept the acarya sampradaya; otherwise one’s endeavor will be futile. Srila Narottama dasa Thakura therefore sings:
tandera carana sevi bhakta sane vasa
 janame janame haya, ei abhilasa
One must worship the lotus feet of the acarya and live within the society of devotees. Then one’s endeavor to cross over nescience will surely be successful.
Srimad Bhagavatam Canto 10, Chapter 02, Text 30
Srimad Bhagavatam Canto 10, Chapter 02, Text 32