In the Ādi Purāṇa there is the following statement by Lord Kṛṣṇa Himself, addressed to Arjuna: "My dear Pārtha, one who claims to be My devotee is not so. Only a person who claims to be the devotee of My devotee is actually My devotee." No one can approach the Supreme Personality of Godhead directly. One must approach Him through His pure devotees. Therefore, in the system of Vaiṣṇava activities, the first duty is to accept a devotee as spiritual master and then to render service unto him.
Śrī Rūpa Gosvāmī affirms that all the quotations given in the Bhakti-rasāmṛta-sindhu from different scriptures are accepted by the great ācāryas and devotees of the Lord.
In the Padma Purāṇa there is a statement that one should perform the ceremonies for the Lord according to one's financial position. Everyone should observe the different ceremonies and celebrations of the Lord by all means. One of the most important of these ceremonial functions is called Ūrja-vrata. Ūrja-vrata is observed in the month of Kārttika (October-November); especially in Vṛndāvana, there is a specific program for temple worship of the Lord in His Dāmodara form. Dāmodara refers to Kṛṣṇa's being bound with rope by His mother, Yaśodā. It is said that just as Lord Dāmodara is very dear to His devotees so the month known as Dāmodara or Kārttika is also very dear to them.
The execution of devotional service during Ūrja-vrata in the month of Kārttika is especially recommended to be performed at Mathurā. This system is still followed by many devotees. They go to Mathurā or Vṛndāvana and stay there during the month of Kārttika specifically to perform devotional services during this period.
In the Padma Purāṇa it is said: "The Lord may offer liberation or material happiness to a devotee, but after some devotional service has been executed, particularly in Mathurā during the month of Kārttika, the devotees want only to attain pure devotional service unto the Lord." The purport is that the Lord does not award devotional service to ordinary persons who are not serious about it. But even such unserious persons who execute devotional service according to the regulative principles during the month of Kārttika, and within the jurisdiction of Mathurā in India, are very easily awarded the Lord's personal service.
In the Bhaviṣya Purāṇa there is a statement about observing different ceremonies celebrating the Lord's appearance (birthday) and other transcendental activities. It is said, "My Lord Janārdana (Kṛṣṇa), please let us know the date when Your mother Devakī devī gave birth to You. If You kindly inform us about this, then we shall observe a great celebration on this date. O killer of Keśī, we are souls one hundred percent surrendered unto Your lotus feet, and we wish only to please You with our ceremonies."
This statement of the Bhaviṣya Purāṇa gives evidence that by observing different functions in relationship with the Lord one is sure to become pleasing to the Lord. It is said in the Ādi Purāṇa: "A person who is constantly engaged in chanting the holy name and who feels transcendental pleasure, being engaged in devotional service, is certainly awarded the facilities of devotional service, and is never given just mukti (liberation)."